Publications by authors named "Roxana Marino"

28 Publications

  • Page 1 of 1

Comprehensive identification of pathogenic gene variants in patients with neuroendocrine disorders.

J Clin Endocrinol Metab 2021 Mar 17. Epub 2021 Mar 17.

Instituto de Biociencias, Biotecnología y Biología Traslacional (IB3), Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad de Buenos Aires, Argentina.

Purpose: Congenital hypopituitarism (CH) can present in isolation or with other birth defects. Mutations in multiple genes can cause CH, and the use of a genetic screening panel could establish the prevalence of mutations in known and candidate genes for this disorder. It could also increase the proportion of patients that receive a genetic diagnosis.

Methods: We conducted target panel genetic screening using single-molecule molecular inversion probes sequencing to assess the frequency of mutations in known hypopituitarism genes and new candidates in Argentina. We captured genomic DNA from 170 pediatric patients with CH, either alone or with other abnormalities. We performed promoter activation assays to test the functional effects of patient variants in LHX3 and LHX4.

Results: We found variants classified as pathogenic, likely pathogenic or with uncertain significance in 15.3% of cases. These variants were identified in known CH causative genes (LHX3, LHX4, GLI2, OTX2 and HESX1), in less frequently reported genes (FOXA2, BMP4, FGFR1, PROKR2, PNPLA6) and in new candidate genes (BMP2, HMGA2, HNF1A, NKX2-1).

Conclusion: In this work, we report the prevalence of mutations in known CH genes in Argentina and provide evidence for new candidate genes. We show that CH is a genetically heterogeneous disease with high phenotypic variation and incomplete penetrance, and our results support the need for further gene discovery for CH. Identifying population-specific pathogenic variants will improve the capacity of genetic data to predict eventual clinical outcomes.
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http://dx.doi.org/10.1210/clinem/dgab177DOI Listing
March 2021

Ehlers-Danlos syndrome: molecular and clinical characterization of TNXA/TNXB chimeras in congenital adrenal hyperplasia.

J Clin Endocrinol Metab 2021 Jan 22. Epub 2021 Jan 22.

Endocrinology Service, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires.

Context: The syndrome CAH-X is due to a contiguous gene deletion of CYP21A2 and TNXB resulting in TNXA/TNXB chimeras.

Objective: To analyze TNXB gene status and to clinically evaluate the Ehlers-Danlos syndrome phenotype in a large cohort of Argentine congenital adrenal hyperplasia (CAH) patients to assess the prevalence of this condition in our population.

Design, Settings, Participants, Intervention: TNXB-gene analysis was performed in 66 non-related CAH patients that were carriers of the CYP21A2 gene deletion. A molecular strategy based on Multiplex ligation-dependent probe amplification and Sanger sequencing analysis was developed allowing for the detection of different, previously described TNXA/TNXB chimeras, named CH1, CH2, and CH3.

Main Outcome Measures: TNXB status of CAH patients that were carriers of the CYP21A2 deletion in the homozygous or heterozygous state.

Results: TNXA/TNXB CH1 was found in 41%, CH2 in 29% and CH3 in 1.5% of non-related alleles carrying the CYP21A2 deletion. Thus, overall 71% of alleles were found to carry a contiguous gene deletion. 67% of patients analyzed had a monoallelic and 6% a biallelic form. All patients with the biallelic form had severe skin hyperextensibility and generalized joint hypermobility.

Conclusions: Based on the high frequency of TNXB alterations in CYP21A2-deletion carrier alleles found, we recommend to evaluate TNXB status in these patients, and to assess connective tissue dysplasia including cardiologic alterations in positive cases. The number of patients undergoing cardiological evaluation should be expanded to determine the incidence of structural and functional abnormalities in this cohort.
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http://dx.doi.org/10.1210/clinem/dgab033DOI Listing
January 2021

Classical congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OHD) in adult males: Clinical presentation, hormone function and the detection of adrenal and testicular adrenal rest tumors (TARTs).

Endocrinol Diabetes Nutr 2021 Apr 11;68(4):227-235. Epub 2020 Dec 11.

Department of Endocrinology, Hospital JM Ramos Mejía, Urquiza 609, Zip Code 1221, Buenos Aires, Argentina.

Introduction: 21-hydroxylase deficiency (21-OHD) is the most common form of congenital adrenal hyperplasia (CAH). In adulthood, most studies are reported in females. By contrast, data on adult males are scarce.

Objective: To describe a series of adult males with classic 21-OHD and to assess the presence of adrenal masses and testicular adrenal rest tumors (TARTs).

Material And Methods: Eight males (21-42 years) were included. We evaluated clinical presentation, 17-Hydroxyprogesterone (17-OHP), Testosterone (T), Δ4Androstenedione (Δ4A) ACTH, LH, FSH and plasma renin activitiy (PRA) levels at consultation. Molecular studies of the CYP21A2 gene, testicular ultrasound (US), semen analysis and adrenal computed tomography (CT) scan were performed. Treatment and compliance were assessed.

Results: Basal 17-OHP levels were >20ng/ml in all patients. At consultation, median 17OH-P was 11.5 (2.3-81) ng/ml, FSH: 3 (0.3-4) mUI/ml, LH: 1.1 (0.1-6) mUI/ml, T: 4.3 (1.7-8) ng/ml, Δ4A: 5.7 (1.4-16) ng/ml, ACTH: 86.4 (76-334) pg/ml, PRA: 9.5 (1.3-23.6) ng/ml/h. Semen analysis was performed in 5/8 patients, showing azoospermia in two. Molecular genetic analysis was performed in 4/8 patients. TARTs were found in 5/6, being bilateral in four. Adrenal masses were found in 4/6. In the 7 patients diagnosed in childhood, their follow-up was referred to as irregular, both in their attendance at consultations and in compliance with the indicated treatment.

Conclusions: To our knowledge, this is the first series on adult males with classic 21-OHD which concomitantly assesses clinical presentation, molecular biology, adrenal and testicular imaging studies, semen analysis and compliance to treatment. A high prevalence of adrenal masses and TARTs was observed, possibly associated with poor treatment compliance leading to elevated ACTH and increased proliferation. Our findings on TARTs agree with reports in international publications of CAH in males, with adrenal imaging being added in our group. Although we are aware that further studies with a larger sample size and more data are needed, we consider that our findings contribute to the clinical management of classical 21-OHD in the male population.
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http://dx.doi.org/10.1016/j.endinu.2020.07.006DOI Listing
April 2021

Testis formation in XX individuals resulting from novel pathogenic variants in Wilms' tumor 1 () gene.

Proc Natl Acad Sci U S A 2020 06 3;117(24):13680-13688. Epub 2020 Jun 3.

Human Developmental Genetics Unit, Institut Pasteur, 75724 Paris, France;

Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the testis-determining gene is present in many cases, the etiology is unknown in most -negative patients. We performed exome sequencing on 78 individuals with 46,XX TDSD/OTDSD of unknown genetic etiology and identified seven (8.97%) with heterozygous variants affecting the fourth zinc finger (ZF4) of Wilms' tumor 1 (WT1) (p.Ser478Thrfs*17, p.Pro481Leufs*15, p.Lys491Glu, p.Arg495Gln [x3], p.Arg495Gly). The variants were de novo in six families ( = 4.4 × 10), and the incidence of WT1 variants in 46,XX DSD is enriched compared to control populations ( < 1.8 × 10). The introduction of ZF4 mutants into a human granulosa cell line resulted in up-regulation of endogenous Sertoli cell transcripts and XX mice display masculinization of the fetal gonads. The phenotype could be explained by the ability of the mutated proteins to physically interact with and sequester a key pro-ovary factor β-CATENIN, which may lead to up-regulation of testis-specific pathway. Our data show that unlike previous association of WT1 and 46,XY DSD, ZF4 variants of WT1 are a relatively common cause of 46,XX TDSD/OTDSD. This expands the spectrum of phenotypes associated with WT1 variants and shows that the WT1 protein affecting ZF4 can function as a protestis factor in an XX chromosomal context.
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http://dx.doi.org/10.1073/pnas.1921676117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7306989PMC
June 2020

Molecular analysis of the CYP21A2 gene in dried blood spot samples.

Medicina (B Aires) 2020 ;80(3):197-202

Laboratorio de Pesquisa Neonatal, Laboratorio de Biología Molecular y Diagnóstico, Servicio de Endocrinología, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina. E-mail:

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder due to a deficiency of enzymes involved in cortisol biosynthesis. In more than 90% of cases, CAH is secondary to deleterious mutations in the CYP21A2 gene leading to 21-hydroxilase deficiency (21OHD). The CYP21A2 gene is located on the short arm of chromosome 6 (6p21·3) and encodes the cytochrome P450C21 enzyme. Neonatal screening programs detect the classic forms of CAH-21OHD quantifying 17OH-progesterone in dried blood spots (DBS). This test is very sensitive, but it has a low specificity, requiring a second sample to confirm the result. In these cases, a second-tier test in the same sample may be useful. Our aim was to evaluate a DNA extraction method from DBS and assess the performance of such DNA in the molecular analysis of the CYP21A2 gene mutations. Twelve individuals, who presumably had CAH based on the initial neonatal screening results, were analyzed using DNA extracted from freshly collected blood on EDTA and DBS. The CYP21A2 gene was analyzed by automated sequencing of all exons and intron boundaries and MLPA analysis in DBS. Molecular analysis results from both extraction methods were compared. In this study, we show that DNA extracted from neonatal screening DBS is a useful tool to define CYP21A2 gene mutations in 21-OHD diagnostic confirmation for the newborn screening program and that its results are comparable to traditional genotyping.
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June 2020

Estrogens in Human Male Gonadotropin Secretion and Testicular Physiology From Infancy to Late Puberty.

Front Endocrinol (Lausanne) 2020 25;11:72. Epub 2020 Feb 25.

Endocrinology Department, Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina.

Several reports in humans as well as transgenic mouse models have shown that estrogens play an important role in male reproduction and fertility. Estrogen receptor alpha (ERα) and beta (ERβ) are expressed in different male tissues including the brain. The estradiol-binding protein GPER1 also mediates estrogen action in target tissues. In human testes a minimal ERα expression during prepuberty along with a marked pubertal up-regulation in germ cells has been reported. ERβ expression was detected mostly in spermatogonia, primary spermatocytes, and immature spermatids. In Sertoli cells ERβ expression increases with age. The aromatase enzyme (cP450arom), which converts androgens to estrogens, is widely expressed in human tissues (including gonads and hypothalamus), even during fetal life, suggesting that estrogens are also involved in human fetal physiology. Moreover, cP450arom is expressed in the early postnatal testicular Leydig cells and spermatogonia. Even though the aromatase complex is required for estrogen synthesis, its biological relevance is also related to the regulation of the balance between androgens and estrogens in different tissues. Knockout mouse models of aromatase (ArKO) and estrogen receptors (ERKOα, ERKOβ, and ERKOαβ) provide an important tool to study the effects of estrogens on the male reproductive physiology including the gonadal axis. High basal serum FSH levels were reported in adult aromatase-deficient men, suggesting that estrogens are involved in the negative regulatory gonadotropin feedback. However, normal serum gonadotropin levels were observed in an aromatase-deficient boy, suggesting a maturational pattern role of estrogen in the regulation of gonadotropin secretion. Nevertheless, the role of estrogens in primate testis development and function is controversial and poorly understood. This review addresses the role of estrogens in gonadotropin secretion and testicular physiology in male humans especially during childhood and puberty.
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http://dx.doi.org/10.3389/fendo.2020.00072DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7051936PMC
March 2021

Androgen Insensitivity Syndrome: Clinical Phenotype and Molecular Analysis in a Single Tertiary Center Cohort

J Clin Res Pediatr Endocrinol 2019 02 25;11(1):24-33. Epub 2018 Sep 25.

Hospital de Pediatria Garrahan, Endocrinology Service, Buenos Aires, Argentina

Objective: The aim of this study was the molecular characterization of the gene as the cause of 46,XY disorder in our population.

Methods: We studied 41, non related, 46,XY disorder of sexual differentiation index cases, having characteristics consistent with androgen insensivity syndrome (AIS). Genomic DNA was isolated from peripheral blood leukocytes of all patients and 25 family members from 17 non-related families.

Results: The gene analysis revealed an abnormal sequence in 58.5% of the index patients. All of the complete AIS (CAIS) cases were genetically confirmed, while in the partial form (PAIS) a mutation in was detected in only 13 (43.3%). Molecular studies revealed other affected or carrier relatives in 87% of the index cases. The mutations were found spread along the whole coding sequence, with a higher prevalence in the ligand binding domain. Nine out of 23 (39%) mutations were novel. In 17% of patients with detected mutations, somatic mosaicism was detected in leucocyte DNA. In our cohort, long-term follow up gender dysphoria, raised as male or female, was not found. Finally, in suspected PAIS, the identification of mutation occurred significantly less than in CAIS patients.

Conclusion: Improved knowledge of the components of the complex and signaling network might contribute to long term outcome and genetic counseling in AIS patients.
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http://dx.doi.org/10.4274/jcrpe.galenos.2018.2018.0185DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6398199PMC
February 2019

Accelerated Pubertal Tempo in a 46,XY Aromatase-Deficient Patient.

Horm Res Paediatr 2018 31;90(4):275-282. Epub 2018 Aug 31.

Servicio de Endocrinología, Hospital de Pediatría Garrahan, Buenos Aires, Argentina.

Background: Aromatase deficiency is a rare autosomal recessive disorder. 46,XY-affected patients often remain undiagnosed until late puberty. Only 2 pediatric cases have been reported. Data on pubertal development in affected males are scarce.

Aim: To report the clinical phenotype and hormonal studies of an aromatase-deficient boy during the prepubertal and early pubertal period.

Results: The patient was the older brother of a 46,XX girl with aromatase deficiency. Molecular analysis revealed a previously reported homozygous mutation (Arg192Cys) in the CYP19A1 gene. Pubertal onset was at 9.8 years. At 11.3 years of age, signs of rapidly progressive puberty were seen. Laboratory tests revealed normal pubertal basal and GnRH-stimulated gonadotropin levels, normal Sertoli cell markers, and increased testosterone. The prepubertal lumbar spine bone mineral density (BMD) was normal but pubertal bone mineral accrual was incomplete, leading to osteopenia.

Conclusion: Estrogen restraint on gonadotropin secretion has been demonstrated in animal and human models. Interestingly, our patient presented with accelerated puberty and apparently normal pituitary gonadal function. These findings suggest that aromatase activity may be required to define pubertal progression in boys. Estrogen deficiency due to aromatase deficiency is responsible for insufficient bone mineral accrual during puberty.
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http://dx.doi.org/10.1159/000492128DOI Listing
April 2019

Mutation of HSD3B2 Gene and Fate of Dehydroepiandrosterone.

Vitam Horm 2018 30;108:75-123. Epub 2018 Jun 30.

Endocrine Department, Hospital de Pediatría Garrahan, Buenos Aires, Argentina; National Scientific and Technical Research Council, Buenos Aires, Argentina. Electronic address:

3βHSD2 enzyme is crucial for adrenal and gonad steroid biosynthesis. In enzyme deficiency states, due to recessive loss-of-function HSD3B2 mutations, steroid flux is altered and clinical manifestations result. Deficiency of 3βHSD2 activity in the adrenals precludes normal aldosterone and cortisol synthesis and the alternative backdoor and 11-oxygenated C19 steroid pathways and the flooding of cortisol precursors along the Δ5 pathway with a marked rise in DHEA and DHEAS production. In gonads, it precludes normal T and estrogen synthesis. Here, we review androgen-dependent male differentiation of the external genitalia in humans and link this to female development and steroidogenesis in the developing adrenal cortex. The molecular mechanisms governing postnatal adrenal cortex zonation and ZR development were also revised. This chapter will review relevant clinical, hormonal, and genetic aspects of 3βHSD2 deficiency with emphasis on the significance of alternate fates encountered by steroid hormone precursors in the adrenal gland and gonads. Our current knowledge of the process of steroidogenesis and steroid action is derived from pathological conditions. In humans the 3βHSD2 deficiency represents a model of nature that reinforces our knowledge about the role of the steroidogenic alternative pathway in sex differentiation in both sexes. However, the physiological role of the high serum DHEAS levels in fetal life as well as after adrenarche remains to be elucidated.
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http://dx.doi.org/10.1016/bs.vh.2018.05.002DOI Listing
November 2018

Androgen Insensitivity Syndrome at Prepuberty: Marked Loss of Spermatogonial Cells at Early Childhood and Presence of Gonocytes up to Puberty.

Sex Dev 2017 24;11(5-6):225-237. Epub 2018 Jan 24.

Servicio de Endocrinología, Hospital de Pediatría 'Prof. Dr. Juan Pedro Garrahan', Buenos Aires, Argentina.

Androgen insensitivity syndrome (AIS) is a hereditary condition in patients with a 46,XY karyotype in which loss-of-function mutations of the androgen receptor (AR) gene are responsible for defects in virilization. The aim of this study was to investigate the consequences of the lack of AR activity on germ cell survival and the degree of testicular development reached by these patients by analyzing gonadal tissue from patients with AIS prior to Sertoli cell maturation at puberty. Twenty-three gonads from 13 patients with AIS were assessed and compared to 18 testes from 17 subjects without endocrine disorders. The study of the gonadal structure using conventional microscopy and the ultrastructural characteristics of remnant germ cells using electron microscopy, combined with the immunohistochemical analysis of specific germ cell markers (MAGE-A4 for premeiotic germ cells and of OCT3/4 for gonocytes), enabled us to carry out a thorough investigation of germ cell life in an androgen-insensitive microenvironment throughout prepuberty until young adulthood. Here, we show that germ cell degeneration starts very early, with a marked decrease in number after only 2 years of life, and we demonstrate the permanence of gonocytes in AIS testis samples until puberty, describing 2 different populations. Additionally, our results provide further evidence for the importance of AR signaling in peritubular myoid cells during prepuberty to maintain Sertoli and spermatogonial cell health and survival.
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http://dx.doi.org/10.1159/000486089DOI Listing
October 2018

Two novel heterozygous missense variations within the GLI2 gene in two unrelated Argentine patients.

Medicina (B Aires) 2016;76(4):213-8

Servicio de Endocrinología, Hospital de Pediatría Prof. Dr. Juan P. Garrahan, Buenos Aires, Argentina. E-mail:

Several heterozygous GLI2 gene mutations have been reported in patients with isolated GH deficiency (IGHD) or multiple pituitary hormone deficiency (MPHD) with or without other malformations. The primary aim of this study was to analyze the presence of GLI2 gene alterations in a cohort of patients with IGHD or MPHD and ectopic/absent posterior pituitary. The coding sequence and flanking intronic regions of GLI2 gene were amplified and directly sequenced from gDNA of 18 affected subjects and relatives. In silico tools were applied to identify the functional impact of newly found variants (Polyphen2, SIFT, Mutation Taster). We identified two novel heterozygous missense variations in two unrelated patients, p.Arg231Gln and p.Arg226Leu, located in the repressor domain of the protein. Both variations affect highly conserved amino acids of the Gli2 protein and were not found in the available databases. In silico tools suggest that these variations might be disease causing. Our study suggests that the GLI2 gene may be one of the candidate genes to analyze when an association of pituitary hormone deficiency and developmental defects in posterior pituitary gland. The highly variable phenotype found suggests the presence of additional unknown factors that could contribute to the phenotype observed in these patients.
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February 2017

An Intron 9 CYP19 Gene Variant (IVS9+5G>A), Present in an Aromatase-Deficient Girl, Affects Normal Splicing and Is Also Present in Normal Human Steroidogenic Tissues.

Horm Res Paediatr 2015 5;84(4):275-82. Epub 2015 Aug 5.

Endocrinology Service, Hospital de Pediatrx00ED;a Garrahan, Buenos Aires, Argentina.

Background/aims: Splicing CYP19 gene variants causing aromatase deficiency in 46,XX disorder of sexual development (DSD) patients have been reported in a few cases. A misbalance between normal and aberrant splicing variants was proposed to explain spontaneous pubertal breast development but an incomplete sex maturation progress. The aim of this study was to functionally characterize a novel CYP19A1 intronic homozygote mutation (IVS9+5G>A) in a 46,XX DSD girl presenting spontaneous breast development and primary amenorrhea, and to evaluate similar splicing variant expression in normal steroidogenic tissues.

Methods: Genomic DNA analysis, splicing prediction programs, splicing assays, and in vitro protein expression and enzyme activity analyses were carried out. CYP19A1 mRNA expression in human steroidogenic tissues was also studied.

Results: A novel IVS9+5G>A homozygote mutation was found. In silico analysis predicts the disappearance of the splicing donor site in intron 9, confirmed by patient peripheral leukocyte cP450arom and in vitro studies. Protein analysis showed a shorter and inactive protein. The intron 9 transcript variant was also found in human steroidogenic tissues.

Conclusions: The mutation IVS9+5G>A generates a splicing variant that includes intron 9 which is also present in normal human steroidogenic tissues, suggesting that a misbalance between normal and aberrant splicing variants might occur in target tissues, explaining the clinical phenotype in the affected patient.
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http://dx.doi.org/10.1159/000437142DOI Listing
September 2016

STAT5B mutations in heterozygous state have negative impact on height: another clue in human stature heritability.

Eur J Endocrinol 2015 Sep 1;173(3):291-6. Epub 2015 Jun 1.

Unidade de Endocrinologia GeneticaLaboratorio de Endocrinologia Celular e Molecular LIM/25, Disciplina de Endocrinologia da Faculdade de Medicina da Universidade de Sao Paulo, Avenida Dr Arnaldo, 455 5° Andar Sala 5340, 01246-903 Sao Paulo, Sao Paulo, BrazilDivision of EndocrinologyCincinnati Center for Growth Disorders, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USACentro de Investigaciones Endocrinológicas 'Dr César Bergadá' (CEDIE)CONICET - FEI - División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, ArgentinaEndocrine ServiceHospital de Pediatria Garrahan, Ciudad Autonoma de Buenos Aires Pozos 1881, 1245 Buenos Aires, ArgentinaDivision of EndocrinologyDepartment of Medicine, Leiden University Medical Center, 2300 RC Leiden, The NetherlandsUniversidade do Extremo Sul Catarinense88806-000 Criciúma, Santa Catarina, BrazilDepartment of PediatricsLeiden University Medical Center, 2300 RC Leiden, The NetherlandsDepartment of PediatricsOregon Health and Science University, Portland, Oregon 97239, USA

Context And Objective: GH insensitivity with immune dysfunction caused by STAT5B mutations is an autosomal recessive condition. Heterozygous mutations in other genes involved in growth regulation were previously associated with a mild height reduction. Our objective was to assess for the first time the phenotype of heterozygous STAT5B mutations.

Methods: We genotyped and performed clinical and laboratory evaluations in 52 relatives of two previously described Brazilian brothers with homozygous STAT5B c.424_427del mutation (21 heterozygous). Additionally, we obtained height data and genotype from 1104 adult control individuals from the same region in Brazil and identified five additional families harboring the same mutation (18 individuals, 11 heterozygous). Furthermore, we gathered the available height data from first-degree relatives of patients with homozygous STAT5B mutations (17 individuals from seven families). Data from heterozygous individuals and non-carriers were compared.

Results: Individuals carrying heterozygous STAT5B c.424_427del mutation were 0.6 SDS shorter than their non-carrier relatives (P = 0.009). Heterozygous subjects also had significantly lower SDS for serum concentrations of IGF1 (P = 0.028) and IGFBP3 (P = 0.02) than their non-carrier relatives. The 17 heterozygous first-degree relatives of patients carrying homozygous STAT5B mutations had an average height SDS of -1.4 ± 0.8 when compared with population-matched controls (P < 0.001).

Conclusions: STAT5B mutations in the heterozygous state have a significant negative impact on height (∼ 3.9 cm). This effect is milder than the effect seen in the homozygous state, with height usually within the normal range. Our results support the hypothesis that heterozygosity of rare pathogenic variants contributes to normal height heritability.
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http://dx.doi.org/10.1530/EJE-15-0398DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4898761PMC
September 2015

Gonadoblastoma in patients with Ullrich-Turner syndrome.

Pediatr Dev Pathol 2015 Mar-Apr;18(2):117-21. Epub 2014 Dec 23.

1 Department of Genetics, Laboratory of Cytogenetics, Hospital Nacional de Pediatría J.P Garrahan, Combate de los Pozos 1881 (CP 1245) Buenos Aires, Argentina.

Ullrich-Turner syndrome (UTS) is a common chromosomal abnormality caused by partial or complete X chromosome monosomy. One half of the patients have a 45,X karyotype, whereas the remaining patients display other X chromosome anomalies. In 6% to 11% of UTS, a normal or partly deleted Y chromosome has been found. A 10% to 30% risk of developing gonadoblastoma was found in the latter patients. The aim of this study was to evaluate the prevalence of Y chromosome-derived material, the occurrence of gonadoblastoma, and the incidence of possible neoplasms in patients with UTS. Of 217 patients studied with UTS and chromosome analysis of peripheral-blood lymphocytes, Y chromosome material was found in 20 patients. Fluorescence in situ hybridization (FISH) testing was performed to characterize the structurally abnormal Y chromosome in 13 cases. Molecular analysis of the SRY gene could only be performed in 20 patients with 45,X karyotype. Two patients had the SRY genomes. Of the 20 patients with Y chromosome-derived material, 17 underwent gonadectomy. The incidence of gonadoblastoma development in our series was 35.5%. Furthermore, 1 patient also showed a pure dysgerminoma, and another showed a mixed dysgerminoma and embryonal carcinoma. We emphasize the importance of complete processing of the gonadectomy specimen, including step sections, molecular studies, and FISH, in addition to the classic cytogenetic searching for Y chromosome sequences, in patients who present with a nonmosaic 45,X karyotype. Finally, we propose to routinely collect a sample for storage in the tumor bank for future studies.
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http://dx.doi.org/10.2350/14-08-1539-OA.1DOI Listing
May 2015

Five new cases of 46,XX aromatase deficiency: clinical follow-up from birth to puberty, a novel mutation, and a founder effect.

J Clin Endocrinol Metab 2015 Feb 21;100(2):E301-7. Epub 2014 Nov 21.

Endocrinology Service (R.M., N.P.G., M.Co., G.G., M.J., P.R., D.M.W., M.Ci., M.A.R., A.B., N.S.), Laboratory of Cellular Biology and Retrovirus (C.R.), Hospital de Pediatria Garrahan, C1245AAM Buenos Aires, Argentina; Endocrine Service (G.P.), Hospital Infantil Municipal de Córdoba, 5000 Córdoba, Argentina; Endocrine Service (J.G.F.), Hospital Regional de Concepcion, CPT4146GXD Tucuman, Argentina; and Endocrine Service (M.M.), Hospital de Niños de la Santísima Trinidad de Córdoba, 5000 Córdoba, Argentina.

Context: Aromatase is the key enzyme for estrogen biosynthesis and is encoded by the CYP19A1 gene. Since 1991, several molecular CYP19A1 gene alterations associated with aromatase deficiency have been described in both sexes.

Objective: The objective of the study was to detect CYP19A1 mutations in five aromatase-deficient 46,XX patients, to describe the clinical follow-up from birth to puberty and to perform haplotype analysis associated with the high-frequency c.628G>A splice mutation in Argentinean patients.

Design: The design of the study was the sequencing of the coding and flanking intronic regions of the CYP19A1 gene in all patients and parents. Haplotype analysis of patients carrying the c.628G>A mutation was also performed.

Patients: Clinical and biochemical findings in five new cases and one previously reported female aromatase-deficient patient (46,XX) are described. All patients presented with ambiguous genitalia at birth. Congenital adrenal hyperplasia due to 21-hydroxylase deficiency as well as other steroidogenic defects were ruled out.

Results: Phenotypic variability among the affected patients was found during follow-up. Direct sequencing of the CYP19A1 gene from genomic DNA revealed one novel mutation (c.574C>T) in two patients. In silico analysis predicted the c.574C>T mutation to be probably damaging. Four of six nonrelated patients presented with the c.628G>A splice mutation. Haplotype analysis showed that the c.628G>A splice mutation is associated with the same haplotype in our population.

Conclusions: Increased knowledge on phenotypical variability found in female aromatase-deficient patients is useful to improve the detection rate in this disorder. In our population, a genetic founder defect has probably contributed to an increase in the incidence of the c.628G>A splice mutation.
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http://dx.doi.org/10.1210/jc.2014-2967DOI Listing
February 2015

A novel missense mutation in the HSD3B2 gene, underlying nonsalt-wasting congenital adrenal hyperplasia. new insight into the structure-function relationships of 3β-hydroxysteroid dehidrogenase type II.

J Clin Endocrinol Metab 2015 Jan;100(1):E191-6

Endocrine Service (M.S.B., M.C., R.M., N.P.G., P.R., M.M., M.A.R., A.B.), Hospital de Pediatria Garrahan, CONICET, Buenos Aires, Argentina; Biological Chemistry Department (A.T., L.A.D.), Instituto de Química Física de los Materiales Medio Ambiente y Energia (INQUIMAE)-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.

Context: 3βHSD2 is a bifunctional microsomal NAD+-dependent enzyme crucial for adrenal and gonad steroid biosynthesis, converting Δ5-steroids to Δ4-steroids. 3βHSD2 deficiency is a rare cause of congenital adrenal hyperplasia caused by recessive loss-of-function HSD3B2 mutations.

Objective: The aim was to define the pathogenic consequences of a novel missense mutation in the HSD3B2 gene.

Patient: We report a 7-month-old 46,XX girl referred because of precocious pubarche and postnatal clitoromegaly. Hormonal profile showed inadequate glucocorticoid levels, increased 17OHP and renin levels, and very high DHEAS levels, suggestive of compensated nonsalt-losing 3βHSD2 deficiency.

Design And Results: Direct sequencing revealed a novel, homozygous, pG250V HSD3B2 mutation. In vitro analysis in intact COS-7 cells showed impaired enzymatic activity for the conversion of pregnenolone to progesterone and dehydroepiandrosterone to androstenedione (20% and 27% of WT at 6 h, respectively). G250V-3βHSD2 decreased the Vmax for progesterone synthesis without affecting the Km for pregnenolone. Western blot and immunofluorescence suggested that p.G250V mutation has no effect on the expression and intracellular localization of the mutant protein. Molecular homology modeling predicted that mutant V250 affected an L239-Q251 loop next to a β-sheet structure in the NAD+-binding domain.

Conclusions: We identified a novel p.G250V mutation of HSD3B2 which causes an incomplete loss of enzymatic activity, explaining the compensated nonsalt loss phenotype. In vitro and in silico experiments provided insight into the structure-function relationship of the 3βHSD2 protein suggesting the importance of the L239-Q251 loop for the catalytic activity of the otherwise stable 3βHSD2 enzyme.
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http://dx.doi.org/10.1210/jc.2014-2676DOI Listing
January 2015

Three novel IGF1R mutations in microcephalic patients with prenatal and postnatal growth impairment.

Clin Endocrinol (Oxf) 2015 May 7;82(5):704-11. Epub 2014 Aug 7.

Endocrinology Service, Hospital de Pediatría Garrahan, Buenos Aires, Argentina.

Background: IGF1R gene mutations have been associated with varying degrees of intrauterine and postnatal growth retardation, and microcephaly.

Objective: To identify and characterize IGF1R gene variations in a cohort of 28 Argentinean children suspected of having IGF-1 insensitivity, who were selected on the basis of the association of pre/postnatal growth failure and microcephaly.

Methods: The coding sequence and flanking intronic regions of IGF1R gene were amplified and directly sequenced. Functional characterization was performed by two in vitro assays: 1) [Methyl-(3) H] thymidine incorporation into DNA in fibroblast cell primary cultures from patients and controls treated with IGF-1 for 16-24 h. 2) PI3K/Akt pathway was evaluated with phospho-Akt (Ser473) STAR ELISA Kit (Millipore) in fibroblast cultures from patients and controls stimulated with IGF-1 for 10 min. Prepubertal clinical and GH-IGF-1 axis evaluation was followed up.

Results: We identified three novel heterozygous missense mutations in three unrelated patients, de novo p.Arg1256Ser, de novo p.Asn359Tyr and p.Tyr865Cys. In control cells, proliferation assay showed that IGF-1 significantly induced DNA synthesis at 20 h and Akt phosphorylation assay that it significantly stimulated phosphorylation after 10 min (P < 0·05 by anova and Bonferroni Tests). However, no significant increase was observed in any of the three patient fibroblasts in both functional studies. GH therapy growth response in two patients was inconsistent.

Conclusion: These variations led to failure of the IGF1R function causing pre- and postnatal growth retardation and microcephaly. Microcephaly should be considered in the evaluation of SGA patients, because it seems to favour the frequency of detection of IGF1R mutations.
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http://dx.doi.org/10.1111/cen.12555DOI Listing
May 2015

[Novel heterozygous mutation in the steroidogenic acute regulatory protein gene in a 46,XY patient with congenital lipoid adrenal hyperplasia].

Medicina (B Aires) 2013 ;73(4):297-302

Servicio de Endocrinología, Hospital Nacional de Pediatría Juan P. Garrahan, Buenos Aires, Argentina.

StAR facilitates cholesterol entry into the mitochondria as part of the transduceosome complex. Recessive mutations in the gen STAR cause classic and nonclassic congenital lipoid adrenal hyperplasia. The aim of the study was to analyze the molecular consequences of a novel heterozygous STAR mutation in a 46,XY patient with ambiguous genitalia and adrenal insufficiency. We found a de novo heterozygous IVS-2A>G STAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1 and TSPO genes. RT-PCR and sequencing from patient's testicular RNA showed a -exon2 transcript and the wild-type (WT) transcript. Both 37 kDa precursor and 30 kDa mature protein were detected in COS-7 cell transfected with mutant and WT plasmids. Immunofluorescence showed almost no co-localization of mitochondria and mutant protein (delta22-59StAR). Delta22-59StAR activity was 65±13% of WT. Cotransfection with WT and delta22-59StAR plasmids reduced WT activity by 62.0% ± 13.9. Novel splice-junction heterozygous STAR mutation (IVS-2A>G) resulted in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. A misfolded p.G22_L59delStAR might interfere with WT StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype.
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June 2014

Unique dominant negative mutation in the N-terminal mitochondrial targeting sequence of StAR, causing a variant form of congenital lipoid adrenal hyperplasia.

J Clin Endocrinol Metab 2013 Jan 21;98(1):E153-61. Epub 2012 Nov 21.

Endocrine Service, Hospital de Pediatria Garrahan, Buenos Aires C1245AAM, Argentina.

Context: Steroid acute regulatory (StAR) protein is a mitochondria-targeted protein that is part of the transduceosome complex crucial for transport of cholesterol to mitochondria. Recessive mutations cause classic and nonclassic congenital lipoid adrenal hyperplasia.

Objective: The aim of this study was to report the clinical, hormonal, genetic, and functional data of a novel heterozygous mutation in the StAR gene found in a 46,XY patient with ambiguous genitalia and neonatal severe steroidogenic deficiency.

Patient: Undetectable serum steroids with high ACTH and plasma renin activity but normal acute GnRH response were found in infancy. After gonadectomy (at 3 yr of age), serum LH and testosterone were undetectable, whereas FSH was normal but increased slowly afterward. Estrogen replacement therapy, started at 10.2 yr of age, suppressed gonadotropins (for 2 yr). However, after 1 month off estrogens, the patient showed castrated levels. At 11.9 yr old, after fludrocortisone withdrawal because of hypertension, plasma renin activity and aldosterone remained normal, suggesting mineralocorticoid recovery by a StAR-independent mechanism.

Results: We found a de novo heterozygous IVS-2A>G StAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1, and TSPO genes. The mutant StAR transcript lacked exon 2, resulting in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. In vitro, the mutant protein exhibited reduced StAR activity in a dominant-negative manner and almost no mitochondria localization.

Conclusions: A misfolded p.G22_L59del StAR might interfere with wild-type StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype. We speculated that estrogen might have modulated mineralocorticoid function and pubertal maturation in a human natural model lacking endogenous steroid production.
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http://dx.doi.org/10.1210/jc.2012-2865DOI Listing
January 2013

Preserved fertility in a patient with a 46,XY disorder of sex development due to a new heterozygous mutation in the NR5A1/SF-1 gene: evidence of 46,XY and 46,XX gonadal dysgenesis phenotype variability in multiple members of an affected kindred.

Horm Res Paediatr 2012 14;78(2):119-26. Epub 2012 Aug 14.

Endocrinology Service, Hospital de Pediatría Garrahan, Buenos Aires, Argentina.

In humans, steroidogenic factor 1 (NR5A1/SF-1) mutations have been reported to cause gonadal dysgenesis, with or without adrenal failure, in both 46,XY and 46,XX individuals. We have previously reported extreme within-family variability in affected 46,XY patients. Even though low ovarian reserve with preserved fertility has been reported in females harboring NR5A1 gene mutations, fertility has only been observed in one reported case in affected 46,XY individuals. A kindred with multiple affected members presenting gonadal dysgenesis was studied. Four 46,XY individuals presented severe hypospadias at birth, one of them associated with micropenis and cryptorchidism. The other 3 developed spontaneous male puberty, and 1 has fathered 5 children. Four 46,XX patients presented premature ovarian failure (one of them was not available for the study) or high follicle-stimulating hormone levels. Mutational analysis of the NR5A1 gene revealed a novel heterozygous mutation, c.938G→A, predicted to cause a p.Arg313Hys amino acid change. A highly conserved amino acid of the ligand-binding domain of the mature protein is affected, predicting abnormal protein function. We confirm that preserved fertility can be observed in patients with a 46,XY disorder of sex development due to heterozygous mutations in the NR5A1 gene.
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http://dx.doi.org/10.1159/000338346DOI Listing
February 2013

Steroid 21-hydroxylase gene mutational spectrum in 454 Argentinean patients: genotype-phenotype correlation in a large cohort of patients with congenital adrenal hyperplasia.

Clin Endocrinol (Oxf) 2011 Oct;75(4):427-35

Endocrinology Service, Hospital de Pediatria Garrahan, Buenos Aires, Argentina.

Objective: To report genotype-phenotype correlation in a large cohort of patients.

Context: Study of the CYP21A2 gene in 866 unrelated chromosomes of 21-hydroxylase deficiency in Argentinean patients with classic and nonclassic (NC) forms of congenital adrenal hyperplasia (CAH).

Methods: Eleven most common mutations were analysed by allele-specific polymerase chain reaction, restriction fragment length polymorphism (RFLP) or southern blot analysis. Gene sequencing was performed when no mutation was detected in one allele or the genotype-phenotype correlation was lacking.

Results: The 11-most-common-mutation screening allowed for the detection of 88·1% of affected alleles (80·3% in the NC and 95·2% in the classic forms). p.V281L, IVS2-13A/C>G (In2) and gene deletions and large gene conversions were the most prevalent mutations. In2 (35·2%) in salt wasting (SW), p.I172N (37·3%) in simple virilizing and p.V281L (54·1%) in NC CAH were the most prevalent mutations within the clinical forms. In 7/15 p.P30L mutation alleles, a chimeric CYP21A1P/CYP21A2 gene [PromCYP21A1P; p.P30L] was detected, while 6/15 represented a single-nucleotide substitution, and in 2/15 linkage with mutations, p.[P30L; V281L] and [p.P30L; IVS2-13A/C > G; p.Q318X] was found. In two SW patients, a novel nonsense mutation, p.Q41X, was observed. In three p.V281L mutation patients, the phenotype was more severe than predicted by genotype. Sequence analysis revealed an intronic alteration in the allele carrying the p.V281L mutation [IVS2 + 5G > A; p.V281L]. An aberrant splicing in this p.V281L mutated allele explains the clinical phenotype.

Conclusions: A high percentage of CYP21A2 affected alleles is detected by the 11-mutation screening study. Genotype-phenotype correlation was high, but when the phenotype is more severe than predicted by genotype, presence of two alterations in one allele should be ruled out.
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http://dx.doi.org/10.1111/j.1365-2265.2011.04123.xDOI Listing
October 2011

Three new SF-1 (NR5A1) gene mutations in two unrelated families with multiple affected members: within-family variability in 46,XY subjects and low ovarian reserve in fertile 46,XX subjects.

Horm Res Paediatr 2011 22;75(1):70-7. Epub 2010 Sep 22.

Endocrinology Service, Hospital de Pediatria Garrahan, Buenos Aires, Argentina.

Background: Three novel heterozygous SF-1 gene mutations affecting multiple members of two unrelated families with a history of 46,XY disorders of sex development (DSD) and 46,XX ovarian insufficiency are described.

Methods: clinical and mutational analysis of the SF-1 gene in 9 subjects of two families.

Results: family 1 had 2 affected 46,XY DSD subjects. One, born with severe perineal hypospadias, was raised as a male, and presented normal adolescence. The other, born with ambiguous genitalia, uterus, and mild testicular dysgenesis, was raised as a female. A W279X heterozygous mutation and an intronic deletion (g3314-3317delTCTC (IVS 4 + 8) was found in the SF-1 gene. In family 2, 4/6 affected siblings had 46,XY DSD or hypospadias. An affected 46,XX sister had normal sexual development but increased FSH levels. The 37-year-old affected mother had entered menopause. An Y183X heterozygous mutation was detected.

Conclusion: an extreme within-family phenotypic variability, ranging from severe prenatal undervirilization to normal pubertal development, was observed in 46,XY-affected siblings, indicating that other unknown factors might be involved in the phenotype. Low ovarian reserve and preserved fertility in 46,XX subjects can be observed in heterozygous SF-1 gene mutations.
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http://dx.doi.org/10.1159/000320029DOI Listing
May 2011

A new DAX-1 mutation in a family with a case of neonatal adrenal insufficiency and a sibling with adrenal hypoplasia and sudden death at 3 years of age.

J Pediatr Endocrinol Metab 2007 Sep;20(9):1039-43

Institute of Maternal and Child Research, Faculty of Medicine, University of Chile, Santiago.

Adrenal hypoplasia congenita (AHC) is a hereditary disorder that leads to adrenal insufficiency and hypogonadotropic hypogonadism (HHG) in childhood. The gene responsible for the X-linked form of AHC, DAX1 (dosage-sensitive sex-reversal, AHC, on the X-chromosome, gene 1)/NR0B1, encodes for a nuclear factor which lacks the characteristic zinc finger DNA-binding domain that is highly conserved in nuclear receptors. Deletions and point mutations in the DAX1 gene have been described in more than 70 AHC families. We present the clinical and genetic data of two brothers affected by AHC. We report a new DAX1 gene mutation in a family with two affected members: one with neonatal adrenal insufficiency, and a sibling with adrenal hypoplasia and sudden death at 3 years old. The NR0B1/DAX1 gene was amplified in three PCR fragments from the patient's and mother's gDNA extracted from peripheral lymphocytes. Sequencing revealed a novel single nucleotide deletion in codon 419 from exon 2 that resulted in a frameshift and a stop codon 17 nucleotides downstream (c.1256 delA). The mother was heterozygous for this mutation. In conclusion, a novel DAX-1 mutation was detected in two family members with different phenotype: one live infant with adrenal hypoplasia, his mother, and probably his dead brother.
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http://dx.doi.org/10.1515/jpem.2007.20.9.1039DOI Listing
September 2007

The cytochrome P450 aromatase lacking exon 5 is associated with a phenotype of nonclassic aromatase deficiency and is also present in normal human steroidogenic tissues.

Clin Endocrinol (Oxf) 2007 Nov 2;67(5):698-705. Epub 2007 Jul 2.

Molecular Biology Laboratory, Endocrinology Department, J. P. Garrahan Paediatric Hospital, Buenos Aires, Argentina.

Objective: The previously described c655G>A mutation of the human cytochrome P450 aromatase gene (P450aro, CYP19) results in aberrant splicing due to disruption of a donor splice site. To explain the phenotype of partial aromatase deficiency observed in a female patient described with this mutation, molecular consequences of the c655G>A mutation were investigated.

Design: To investigate whether the c655G>A mutation causes an aberrant spliced mRNA lacking exon 5 (-Ex5), P450aro RNA was analysed from the patient's lymphocytes by reverse transcription polymerase chain reaction (RT-PCR) and by splicing assays performed in Y1 cells transfected with a P450aro -Ex5 expression vector. Aromatase activity of the c655G>A mutant was predicted by three dimensional (3D) protein modelling studies and analysed in transiently transfected Y1 cells. Exon 5 might be predicted as a poorly defined exon suggesting a susceptibility to both splicing mutations and physiological alternative splicing events. Therefore, expression of the -Ex5 mRNA was also assessed as a possibly naturally occurring alternative splicing transcript in normal human steroidogenic tissues.

Patients: An aromatase deficient girl was born with ambiguous genitalia. Elevated serum LH, FSH and androgens, as well as cystic ovaries, were found during prepuberty. At the age of 8.4 years, spontaneous breast development and a 194.6 pmol/l serum oestradiol level was observed.

Results: The -Ex5 mRNA was found in lymphocytes of the P450aro deficient girl and her father, who was a carrier of the mutation. Mutant minigene expression resulted in complete exon 5 skipping. As expected from 3D protein modelling, -Ex5 cDNA expression in Y1 cells resulted in loss of P450aro activity. In addition, the -Ex5 mRNA was present in placenta, prepubertal testis and adrenal tissues.

Conclusions: Alternative splicing of exon 5 of the CYP19 gene occurs in the wild type (WT) as well as in the c655G>A mutant. We speculate that for the WT it might function as a regulatory mechanism for aromatization, whereas for the mutant a relative prevalence of the shorter over the full-length protein might explain the phenotype of partial aromatase deficiency.
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http://dx.doi.org/10.1111/j.1365-2265.2007.02948.xDOI Listing
November 2007

Characterization of immunodeficiency in a patient with growth hormone insensitivity secondary to a novel STAT5b gene mutation.

Pediatrics 2006 Nov 9;118(5):e1584-92. Epub 2006 Oct 9.

Hospital de Pediatría Garrahan, Immunology Service, Combate de los Pozos 1881, C1245AAM Buenos Aires, Argentina.

STAT5 proteins are components of the common growth hormone and interleukin 2 family of cytokines' signaling pathway. Mutations in the STAT5b gene, described in 2 patients, lead to growth hormone insensitivity that resembles Laron syndrome. Clinical immunodeficiency was also present, although immunologic defects have not been well characterized thus far. Here we describe a 16-year-old girl who suffered generalized eczema and recurrent infections of the skin and respiratory tract since birth. She also suffered severe chronic lung disease and multiple episodes of herpetic keratitis. Clinical features of congenital growth hormone deficiency were observed, such as persistently low growth rate, severely delayed bone age, and postnatal growth failure resulting from growth hormone resistance. This combined phenotype of growth hormone insensitivity and immunodeficiency was attributable to a homozygous C-->T transition that resulted in a nonsense mutation at codon 152 in exon 5 of the STAT5b gene. This novel mutation determined a complete absence of protein expression. The main immunologic findings were moderate T-cell lymphopenia (1274/mm3), normal CD4/CD8 ratio, and very low numbers of natural killer (18/mm3) and gammadelta T (5/mm3) cells. T cells presented a chronically hyperactivated phenotype. In vitro T-cell proliferation and interleukin 2 signaling were impaired. CD4+ and CD25+ regulatory T cells were significantly diminished, and they probably contributed to the signs of homeostatic mechanism deregulation found in this patient. This new case, in accordance with 2 previously reported cases, definitely demonstrates the significant role of the STAT5b protein in mediating growth hormone actions. Furthermore, the main immunologic findings bring about an explanation for the clinical immunodeficiency features and reveal for the first time the relevant role of STAT5b as a key protein for T-cell functions in humans.
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http://dx.doi.org/10.1542/peds.2005-2882DOI Listing
November 2006

Hypothalamic-pituitary-ovarian axis during infancy, early and late prepuberty in an aromatase-deficient girl who is a compound heterocygote for two new point mutations of the CYP19 gene.

J Clin Endocrinol Metab 2003 Nov;88(11):5127-31

Laboratorio de Investigación, Hospital de Pediatría Garrahan, Buenos Aires, Argentina 1245.

A loss of function mutation of the CYP19 aromatase gene leads to excess circulating androgens in the fetus and in the mother, resulting in ambiguous genitalia in the female fetus. Later on, lack of aromatase is responsible for sexual infantilism, primary amenorrhea, tall stature, and multicystic ovaries, even in preadolescent girls. Up to now, 11 CYP19 aromatase point mutations and 10 well-documented cases have been reported. In the present case, we are reporting the clinical and hormonal follow-up, from birth to 7 yr of age, of an affected girl with ambiguous genitalia. Gene analysis showed that she was a compound heterozygote for two new CYP19 aromatase point mutations. In the father's allele, there was a consensus 5' splice donor sequence mutation, GAA-AAA at cDNA position bp 655 in exon 5, which probably results in a cryptic donor site. In the mother's allele, there was a base A deletion in exon 9 (Delta A GLU 412X), causing a frame shift mutation, and a stop codon after 98 bp (33 codons) downstream, altering the critical heme-binding region. Basal serum LH and FSH levels were high at 8 d of age (42.9 and 51.3 U/liter), 26 d of age (76.2 and 119 U/liter), and 60 d of age (58.7 and 150 U/liter, respectively). Both gonadotropins dropped dramatically between the second and fifth months of age (to 1.79 and 14.9 U/liter) but remained higher than in normal control girls (0.64 and 8.5 U/liter, respectively). Serum testosterone (T) and androstenedione (Delta(4)A) levels were high during the first month, but Delta(4)A was normal at 2 months of age. However, at 5 months of age, along with significant decrements of serum LH and FSH levels and increments in serum Delta(4)A and T levels, a large ovarian cyst was removed from each gonad. Relatively high levels of T [27.3 ng/ml (94.6 nmol/liter); control, 34.9 ng/ml (121 nmol/liter)], but not of estradiol [1.8 ng/ml (6.6 nmol/liter); control 62.9 ng/ml (231 nmol/liter)], and a high T/estradiol ratio [15.2; control < 1] were found in the follicular fluid. Serum Delta(4)A and T levels remained normal from 1-5 yr of age, but they were high at the last visit (late prepuberty). A GnRH test was performed at 3.9, 6, and 7.1 yr of age. At 3.9 yr, a low prepubertal serum LH peak (2.12 U/liter) was found, but at the older ages, higher serum LH peaks (8.25 and 22.5 U/liter, respectively) were observed. Growth pattern and body mass index were normal, but after the age of 5.2 yr, delays in bone age greater than 2 yr were observed. We concluded that: 1) these two new CYP19 aromatase gene mutations are responsible for the phenotype of aromatase deficiency; 2) in girls, aromatase deficiency results in a decrease of the negative feedback of both serum LH and FSH, which can be detected as early as the second week after birth and persists up to the sixth month of life, and of FSH during the rest of prepuberty; and 3) because large ovarian cysts developed when serum LH and FSH dropped, aromatization of androgens might be required to prevent formation of cystic ovaries.
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http://dx.doi.org/10.1210/jc.2003-030433DOI Listing
November 2003