Publications by authors named "Alicia Belgorosky"

68 Publications

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

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

Predictive outcome measures of adult short stature in patients with severe acquired autoimmune hypothyroidism.

Arch Argent Pediatr 2019 12;117(6):388-391

Servicio de Endocrinología Infantil, Hospital de Pediatría Prof. Juan P. Garrahan, Ciudad Autónoma de Buenos Aires.

Hypothyroidism caused by Hashimoto's thyroiditis is the most common reason for thyroid dysfunction in children. Our objective was to analyze its impact on final stature in relation to height and pubertal stage at the time of diagnosis in children younger than 18 years with severe autoimmune hypothyroidism. Out of 79 patients, 78.5 % were girls. Those with goiter (56 %) had a better height at diagnosis than those without goiter (mean standard deviation score for height: 0.2 versus -2.42; p < 0.0001). Five girls (6.3 %) had precocious puberty. When considering the final stature of patients (n: 33), among those with short stature at the time of diagnosis, pubertal children had a significantly shorter final stature than prepubertal children (mean standard deviation score for height: -2.82 versus -1.52; p = 0.0311). The late diagnosis of severe hypothyroidism in pediatrics has a negative impact on final stature, especially in those who were pubertal patients at the time of diagnosis.
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http://dx.doi.org/10.5546/aap.2019.eng.388DOI Listing
December 2019

The Low-Dose ACTH Test: Usefulness of Combined Analysis of Serum and Salivary Maximum Cortisol Response in Pediatrics.

J Clin Endocrinol Metab 2019 10;104(10):4323-4330

Servicio de Endocrinologia, Hospital de Pediatria Garrahan, Buenos Aires, Argentina.

Context: The low-dose (1 µg) ACTH test (LDT) is widely used to assess central adrenal insufficiency (CAI); however, the serum cortisol cutoff value is controversial. Salivary cortisol (SC) may be a more accurate measurement for CAI.

Objective: To assess a new maximum cutoff value of serum cortisol after LDT in pediatric patients, taking into account serum and SC measurements.

Design And Setting: Prospective study in a pediatric tertiary referral center.

Working Hypothesis: The combined analysis of serum and SC response to LDT might improve LDT for CAI diagnosis.

Participant And Outcome Measurement: A total of 145 pediatric patients underwent LDT. Serum and SC levels were measured. A central adrenal sufficient (CAS) response was established according to the reference serum cortisol cutoff value of ≥497 nmol/L.

Results: The LDT study showed central adrenal sufficiency in 72 patients and CAI in 73 patients. Considering the lower quartile of maximum SC value (21 nmol/L) in the CAS group, an intermediate CAI (InCAI) group and a real CAI (RCAI) group were defined. Regarding the median maximum value of serum cortisol levels in the InCAI group, a new serum cortisol cutoff value of 450 nmol/L was established. Furthermore, 91% of the patients in the RCAI group were below this cutoff value.

Conclusion: The combined evaluation of maximum serum and SC levels to LDT might be useful to define an InCAI group and to avoid unnecessary hormone replacement therapy. However, rigorous patient follow-up is required.
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http://dx.doi.org/10.1210/jc.2019-00304DOI Listing
October 2019

[Muscle weakness with hypokalemia and hyperthyroidism in an adolescent with Down syndrome].

Arch Argent Pediatr 2019 02;117(1):e37-e40

Servicio de Endocrinología, Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina.

Acute hypokalemic paralysis is a rare cause of acute weakness. Thyrotoxic periodic paralysis (TPP) is an unusual complication of hyperthyroidism. It is characterized by sudden onset of hypokalemia condition resulting from a shift of potassium into cells and paralysis that primarily affects the lower extremities. Failure to recognize TPP may lead to improper management. Treatment of TPP includes replacing potassium rapidly, using nonselective beta-blockers and correcting the underlying hyperthyroidism as soon as possible. TPP is curable once euthyroid state is achieved. We describe a 13-year-old male with Down syndrome who presented with acute onset of lower extremity weakness secondary to acute hypokalemia and was found to have new onset Graves' disease.
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http://dx.doi.org/10.5546/aap.2019.e37DOI Listing
February 2019

Gonadotrophin-mediated miRNA expression in testis at onset of puberty in rhesus monkey: predictions on regulation of thyroid hormone activity and DLK1-DIO3 locus.

Mol Hum Reprod 2019 03;25(3):124-136

Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine and Magee-Womens Research Institute, 204 Craft Avenue, Pittsburgh, PA, USA.

Molecular mechanisms responsible for the initiation of primate spermatogenesis remain poorly characterized. Previously, 48 h stimulation of the testes of three juvenile rhesus monkeys with pulsatile LH and FSH resulted in down-regulation of a cohort of genes recognized to favor spermatogonia stem cell renewal. This change in genetic landscape occurred in concert with amplification of Sertoli cell proliferation and the commitment of undifferentiated spermatogonia to differentiate. In this report, the non-protein coding small RNA transcriptomes of the same testes were characterized using RNA sequencing: 537 mature micro-RNAs (miRNAs), 322 small nucleolar RNAs (snoRNAs) and 49 small nuclear RNAs (snRNAs) were identified. Pathway analysis of the 20 most highly expressed miRNAs suggested that these transcripts contribute to limiting the proliferation of the primate Sertoli cell during juvenile development. Gonadotrophin treatment resulted in differential expression of 35 miRNAs, 12 snoRNAs and four snRNA transcripts. Ten differentially expressed miRNAs were derived from the imprinted delta-like homolog 1-iodothyronine deiodinase 3 (DLK1-DIO3) locus that is linked to stem cell fate decisions. Four gonadotrophin-regulated expressed miRNAs were predicted to trigger a local increase in thyroid hormone activity within the juvenile testis. The latter finding leads us to predict that, in primates, a gonadotrophin-induced selective increase in testicular thyroid hormone activity, together with the established increase in androgen levels, at the onset of puberty is necessary for the normal timing of Sertoli cell maturation, and therefore initiation of spermatogenesis. Further examination of this hypothesis requires that peripubertal changes in thyroid hormone activity of the testis of a representative higher primate be determined empirically.
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http://dx.doi.org/10.1093/molehr/gay054DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6396851PMC
March 2019

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

Human Adrenal Cortex: Epigenetics and Postnatal Functional Zonation.

Horm Res Paediatr 2018 9;89(5):331-340. Epub 2018 May 9.

The human adrenal cortex, involved in adaptive responses to stress, fluid homeostasis, and secondary sexual characteristics, arises from a tightly regulated development of a zone and cell type-specific secretory pattern. However, the molecular mechanisms governing adrenal zonation, particularly postnatal zona reticularis development, which produce adrenal androgens in a lifetime-specific manner, remain poorly understood. Epigenetic events, including DNA and histone modifications as well as regulation by noncoding RNAs, are crucial in establishing or maintaining the expression pattern of specific genes and thus contribute to the stability of a specific differentiation state. Emerging evidence points to epigenetics as another regulatory layer that could contribute to establishing the adrenal zone-specific pattern of enzyme expression. Here, we outline the developmental milestones of the human adrenal cortex, focusing on current advances and understanding of epigenetic regulation of postnatal functional zonation. Numerous questions remain to be addressed emphasizing the need for additional investigations to elucidate the role of epigenetics in the human adrenal gland. Ultimately, improved understanding of the epigenetic factors involved in adrenal development and function could lead to novel therapeutic interventions.
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http://dx.doi.org/10.1159/000487995DOI Listing
October 2018

[Atypical presentation of a giant prolactinoma in a 15-year-old boy].

Arch Argent Pediatr 2018 Apr;116(2):e325-e330

Servicio de Endocrinología, Hospital de Pediatría "Profesor Dr. Juan P. Garrahan", Ciudad Autónoma de Buenos Aires, Argentina.

Giant prolactinomas are rare pituitary adenomas characterized by their great local invasion. In this paper, we report a 15-year-old male with left retro-ocular pain and ipsilateral exophthalmos of 4 months of evolution, secondary to a tumour in the base of the skull that invaded the orbit. Hormonal studies revealed serum prolactin of 6913,7 ng/ml (normal value < 20), confirming the diagnosis of giant prolactinoma. The patient started treatment with the dopaminergic agonist cabergoline in increasing doses. After 7 months of follow-up the prolactin had decreased to 349.8 ng/ml and the tumor volume was reduced by 70%, without presenting adverse effects to the treatment. The patient was asymptomatic and had restarted puberty. The rapid remission of symptoms without the need for invasive treatments underlines the importance of considering the diagnosis of prolactinoma among the possible differential diagnoses of tumor of the skull base.
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http://dx.doi.org/10.5546/aap.2018.e325DOI Listing
April 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

Histamine H4 receptor as a novel therapeutic target for the treatment of Leydig-cell tumours in prepubertal boys.

Eur J Cancer 2018 03;91:125-135

Laboratorio de Endocrinología Molecular y Transducción de Señales, Instituto de Biología y Medicina Experimental (IBYME-CONICET), Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina. Electronic address:

Leydig-cell tumours (LCTs) are rare endocrine tumours of the testicular interstitium, with recent increased incidence. Symptoms include precocious puberty in children; and erectile dysfunction, infertility and/or gynaecomastia, in adults. So far, scientific evidence points to aromatase (CYP19) overexpression and excessive oestrogen and insulin-like growth factor (IGF) -1 production as responsible for Leydig-cell tumourigenesis. LCTs are usually benign; however, malignant LCTs respond poorly to chemo/radiotherapy, highlighting the need to identify novel targets for treatment. Herein, we investigated the potential role of the histamine receptor H4 (HRH4) as a therapeutic target for LCTs using R2C rat Leydig tumour cells, a well-documented in vitro model for Leydigioma. Also, we studied for the first time the expression of CYP19, IGF-1R, oestrogen receptor (ER) α, ERβ, androgen receptor (AR) and HRH4 in human prepubertal LCTs versus normal prepubertal testes (NPTs). HRH4 agonist treatment inhibited steroidogenesis and proliferation in R2C cells and also negatively affected their pro-angiogenic capacity in vitro and in vivo, as assessed by evaluating the proliferative activity of human umbilical vein endothelial cells and by means of the quail chorioallantoic membrane assay, respectively. Moreover, E2 and IGF-1 inhibited HRH4 mRNA and protein levels. In human prepubertal LCTs, CYP19, IGF-1R, ERα and ERβ were overexpressed compared with NPTs. In contrast, HRH4 staining was weak in LCTs, but moderate/strong and confined to the interstitium in NPTs. Importantly, HRH4 was absent or barely detectable in seminiferous tubules or germ cells. Overall, our results point to HRH4 as a novel therapeutic target in LCTs.
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http://dx.doi.org/10.1016/j.ejca.2017.12.003DOI Listing
March 2018

The testicular transcriptome associated with spermatogonia differentiation initiated by gonadotrophin stimulation in the juvenile rhesus monkey (Macaca mulatta).

Hum Reprod 2017 10;32(10):2088-2100

Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine and Magee-Womens Research Institute, Pittsburgh, PA 15213, USA.

Study Question: What is the genetic landscape within the testis of the juvenile rhesus monkey (Macaca mulatta) that underlies the decision of undifferentiated spermatogonia to commit to a pathway of differentiation when puberty is induced prematurely by exogenous LH and FSH stimulation?

Summary Answer: Forty-eight hours of gonadotrophin stimulation of the juvenile monkey testis resulted in the appearance of differentiating B spermatogonia and the emergence of 1362 up-regulated and 225 down-regulated testicular mRNAs encoding a complex network of proteins ranging from enzymes regulating Leydig cell steroidogenesis to membrane receptors, and from juxtacrine and paracrine factors to transcriptional factors governing spermatogonial stem cell fate.

What Is Known Already: Our understanding of the cell and molecular biology underlying the fate of undifferentiated spermatogonia is based largely on studies of rodents, particularly of mice, but in the case of primates very little is known. The present study represents the first attempt to comprehensively address this question in a highly evolved primate.

Study Design, Size, Duration: Global gene expression in the testis from juvenile rhesus monkeys that had been stimulated with recombinant monkey LH and FSH for 48 h (N = 3) or 96 h (N = 4) was compared to that from vehicle treated animals (N = 3). Testicular cell types and testosterone secretion were also monitored.

Participants/materials, Setting, Methods: Precocious testicular puberty was initiated in juvenile rhesus monkeys, 14-24 months of age, using a physiologic mode of intermittent stimulation with i.v. recombinant monkey LH and FSH that within 48 h produced 'adult' levels of circulating LH, FSH and testosterone. Mitotic activity was monitored by immunohistochemical assays of 5-bromo-2'-deoxyuridine and 5-ethynyl-2'-deoxyuridine incorporation. Animals were bilaterally castrated and RNA was extracted from the right testis. Global gene expression was determined using RNA-Seq. Differentially expressed genes (DEGs) were identified and evaluated by pathway analysis. mRNAs of particular interest were also quantitated using quantitative RT-PCR. Fractions of the left testis were used for histochemistry or immunoflouresence.

Main Results And The Role Of Chance: Differentiating type B spematogonia were observed after both 48 and 96 h of gonadotrophin stimulation. Pathway analysis identified five super categories of over-represented DEGs. Repression of GFRA1 (glial cell line-derived neurotrophic factor family receptor alpha 1) and NANOS2 (nanos C2HC-type zinc finger 2) that favor spermatogonial stem cell renewal was noted after 48 and 96 h of LH and FSH stimulation. Additionally, changes in expression of numerous genes involved in regulating the Notch pathway, cell adhesion, structural plasticity and modulating the immune system were observed. Induction of genes associated with the differentiation of spermatogonia stem cells (SOHLH1(spermatogenesis- and oogenesis-specific basic helix-loop-helix 1), SOHLH2 and KIT (V-Kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog)) was not observed. Expression of the gene encoding STRA8 (stimulated by retinoic acid 8), a protein generally considered to mark activation of retinoic acid signaling, was below our limit of detection.

Large Scale Data: The entire mRNA data set for vehicle and gonadotrophin treated animals (N = 10) has been deposited in the GEO-NCBI repository (GSE97786).

Limitations Reasons For Caution: The limited number of monkeys per group and the dilution of low abundance germ cell transcripts by mRNAs contributed from somatic cells likely resulted in an underestimation of the number of differentially expressed germ cell genes.

Wider Implications Of The Findings: The findings that expression of GDNF (a major promoter of spermatogonial stem cell renewal) was not detected in the control juvenile testes, expression of SOHLH1, SOHLH2 and KIT, promoters of spermatogonial differentiation in mice, were not up-regulated in association with the gonadotrophin-induced generation of differentiating spermatogonia, and that robust activation of the retinoic acid signaling pathway was not observed, could not have been predicted. These unexpected results underline the importance of non-human primate models in translating data derived from animal research to the human situation.

Study Funding/competing Interest(s): The work described was funded by NIH grant R01 HD072189 to T.M.P. P.A. was supported by an Endocrine Society Summer Research Fellowship Award and CONICET (Argentine Research Council), S.N. by a grant from Vali-e-Asr Reproductive Health Research Center of Tehran University of Medical Sciences (grant #24335-39-92) to Dr Batool Hosseini Rashidi, and M.P.H. by grants from the National Health and Medical Research Council of Australia, and the Victorian State Government's Operational Infrastructure Support Program. The authors have nothing to disclose.
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http://dx.doi.org/10.1093/humrep/dex270DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5850871PMC
October 2017

Near-adult height in male kidney transplant recipients started on growth hormone treatment in late puberty.

Pediatr Nephrol 2018 Jan 18;33(1):175-180. Epub 2017 Aug 18.

Department of Endocrinology, Hospital Nacional de Pediatria J.P.Garrahan, C. de los Pozos 1881, C1245AAM, Buenos Aires, Argentina.

Background: Growth retardation and its impact on adult height is considered to be one of the most common complications in patients with chronic kidney disease (CKD). Treatment with recombinant human growth hormone (rhGH) has been effective in improving growth in kidney transplantation (KTx) patients, but little data are available on adult height in patients who began rhGh treatment in late puberty.

Methods: Near-adult height was evaluated in 13 KTx patients treated with rhGH [growth hormone group (GHGr); dose 9.33 mg/m per week] for a period of at least 18 months. At initiation of rhGH treatment, testicular volume was >8 ml and serum testosterone was >1 ng/ml compared with the control group (CGr) of ten KTx patients who did not receive rHGH. All subjects were of similar chronological age and bone age and had similar creatinine clearance (CrCl) levels, cumulative corticoid dose, height standard deviation score (SDS), target height SDS, and target height:initial height at the beginning of the study.

Results: Near-adult height was significantly greater in the GHGr than in the CGr (-1.8 ± 0.8 vs. -2.9 ± 1.1; p = 0.018). The difference between initial height and near-adult height in the GHGr revealed a significant height gain (initial height -3.1 ± 1.1; near-adult height -1.8 ± 0.8 SDS, respectively; delta 1.2 ± 0.3; p = 0.021). The CrCl level was not significantly different between the GHGr and CGr at either at study initiation or when attaining near-adult height (p = 0.74 and p = 0.23, respectively).

Conclusions: Treatment with rhGH was effective in improving adult height in KTx patients who began treatment in late puberty, without any effect on renal function.
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http://dx.doi.org/10.1007/s00467-017-3777-2DOI Listing
January 2018

Clinical, genetic, and structural basis of congenital adrenal hyperplasia due to 11β-hydroxylase deficiency.

Proc Natl Acad Sci U S A 2017 03 22;114(10):E1933-E1940. Epub 2017 Feb 22.

Division of Adrenal Steroid Disorders, Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029;

Congenital adrenal hyperplasia (CAH), resulting from mutations in , a gene encoding 11β-hydroxylase, represents a rare autosomal recessive Mendelian disorder of aberrant sex steroid production. Unlike CAH caused by 21-hydroxylase deficiency, the disease is far more common in the Middle East and North Africa, where consanguinity is common often resulting in identical mutations. Clinically, affected female newborns are profoundly virilized (Prader score of 4/5), and both genders display significantly advanced bone ages and are oftentimes hypertensive. We find that 11-deoxycortisol, not frequently measured, is the most robust biochemical marker for diagnosing 11β-hydroxylase deficiency. Finally, computational modeling of 25 missense mutations of revealed that specific modifications in the heme-binding (R374W and R448C) or substrate-binding (W116C) site of 11β-hydroxylase, or alterations in its stability (L299P and G267S), may predict severe disease. Thus, we report clinical, genetic, hormonal, and structural effects of gene mutations in the largest international cohort of 108 patients with steroid 11β-hydroxylase deficiency CAH.
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http://dx.doi.org/10.1073/pnas.1621082114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5347606PMC
March 2017

Predictor Variables of Developing Anterior Pituitary Deficiencies in a Group of Paediatric Patients with Central Diabetes Insipidus and Langerhans Cell Histiocytosis.

Horm Res Paediatr 2017 13;87(1):51-57. Epub 2016 Dec 13.

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

Background: Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder of unknown etiopathogenesis. Central diabetes insipidus (CDI) is the most frequent endocrine manifestation and is a known risk factor for the development of further anterior pituitary hormone deficiencies (APD). However, not all CDI patients develop APD, as observed during prolonged periods of follow-up.

Aim: To find predictors of developing APD in LCH children with CDI followed in our institution.

Methods: We retrospectively analysed 44 patients over a median period (quartiles) of 12.3 years (8.79-14.24). Patients were subdivided into group 1 and group 2, according to absence or presence of APD, respectively. The main variables studied were: (1) chronological age (CA) at LCH diagnosis, (2) the primary site of LCH at diagnosis: low risk (LR) and multisystemic risk organs, and (3) the presence of reactivation.

Results: Multivariate Cox regression analysis showed that APD was positively associated with CA at LCH diagnosis [relative risk (RR) 1.14, p < 0.01], the LR clinical form (RR 8.6, p < 0.03), and negatively associated with the presence of reactivations (RR 0.3, p < 0.01).

Conclusions: Patients with older CA at LCH diagnosis, LR clinical forms, and fewer reactivation episodes might represent a subgroup of paediatric LCH CDI patients with a higher risk of developing APD.
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http://dx.doi.org/10.1159/000452996DOI Listing
April 2017

DNA methylation is not involved in specific down-regulation of HSD3B2, NR4A1 and RARB genes in androgen-secreting cells of human adrenal cortex.

Mol Cell Endocrinol 2017 02 23;441:46-54. Epub 2016 Sep 23.

Endocrine Service-CONICET, Hospital de Pediatria Garrahan, Buenos Aires, Argentina; National Research Council of Argentina (CONICET), Argentina.

We hypothesized that DNA methylation is involved in human adrenal functional zonation. mRNAs expression and methylation pattern of RARB, NR4A1 and HSD3B2 genes in human adrenal tissues (HAT) and in pediatric virilizing adrenocortical tumors (VAT) were analyzed. For analysis of the results samples were divided into 3 age groups according to FeZ involution, pre and post-adrenarche ages. In all HAT, similar RARB mRNA was found including microdissected zona reticularis (ZR) and zona fasciculata, but HSD3B2 and NR4A1 mRNAs were lower in ZR (p < 0.05). NR4A1 and RARB promoters remained unmethylated in HAT and VAT. No adrenal zone-specific differences in NR4A1 methylation were observed. In summary, RARB was not associated with ZR-specific downregulation of HSD3B2 in postnatal human adrenocotical zonation. DNA methylation would not be involved in NR4A1 adrenocortical cell-type specific downregulation. Lack of CpG islands in HSD3B2 suggested that HSD3B2 ZR-specific downregulation would not be directly mediated by DNA methylation.
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http://dx.doi.org/10.1016/j.mce.2016.09.024DOI Listing
February 2017

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

GH deficiency status combined with GH receptor polymorphism affects response to GH in children.

Eur J Endocrinol 2015 Dec 4;173(6):777-89. Epub 2015 Sep 4.

Merck Serono SAGeneva, SwitzerlandDépartement de PédiatrieHôpital Mère-Enfant, Université Claude Bernard, Lyon, FranceFederal State Institution 'Endocrinology Scientific Center of Russian Medical Technology'Moscow, RussiaEndocrine ServiceHospital de Pediatría Garrahan, Ciudad Autónoma de Buenos Aires, Buenos Aires, ArgentinaIRCCS Istituto Giannina Gaslini di GenovaClinica Pediatrica, Università di Genova, Genova, ItalyPediatra d.U. Azienda Ospedaliera Universitaria IntegrataUniversità di Verona, Verona, ItalyManchester Academic Health Sciences CentreRoyal Manchester Children's Hospital, 5th Floor, Oxford Road, Manchester M13 9WL, UK

Meta-analysis has shown a modest improvement in first-year growth response to recombinant human GH (r-hGH) for carriers of the exon 3-deleted GH receptor (GHRd3) polymorphism but with significant interstudy variability. The associations between GHRd3 and growth response to r-hGH over 3 years in relation to severity of GH deficiency (GHD) were investigated in patients from 14 countries. Treatment-naïve pre-pubertal children with GHD were enrolled from the PREDICT studies (NCT00256126 and NCT00699855), categorized by peak GH level (peak GH) during provocation test: ≤4 μg/l (severe GHD; n=45) and >4 to <10 μg/l mild GHD; n=49) and genotyped for the GHRd3 polymorphism (full length (fl/fl, fl/d3, d3/d3). Gene expression (GE) profiles were characterized at baseline. Changes in growth (height (cm) and SDS) over 3 years were measured. There was a dichotomous influence of GHRd3 polymorphism on response to r-hGH, dependent on peak GH level. GH peak level (higher vs lower) and GHRd3 (fl/fl vs d3 carriers) combined status was associated with height change over 3 years (P<0.05). GHRd3 carriers with lower peak GH had lower growth than subjects with fl/fl (median difference after 3 years -3.3 cm; -0.3 SDS). Conversely, GHRd3 carriers with higher peak GH had better growth (+2.7 cm; +0.2 SDS). Similar patterns were observed for GH-dependent biomarkers. GE profiles were significantly different between the groups, indicating that the interaction between GH status and GHRd3 carriage can be identified at a transcriptomic level. This study demonstrates that responses to r-hGH depend on the interaction between GHD severity and GHRd3 carriage.
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http://dx.doi.org/10.1530/EJE-15-0474DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4623334PMC
December 2015

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

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

Central adrenal insufficiency could not be confirmed by measurement of basal serum DHEAS levels in pubertal children.

Horm Res Paediatr 2014 24;82(5):332-7. Epub 2014 Oct 24.

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

Background: Central adrenal insufficiency (CAI) is due to a decrease of CRH and/or ACTH secretion. ACTH-dependent dehydroepiandrosterone sulphate (DHEAS) has been postulated as a possible marker of adrenal function in adult patients.

Aims: To evaluate the usefulness of basal serum DHEAS determination to diagnose CAI in pubertal patients with a suspected diagnosis of CAI.

Methods: Ninety-four pubertal patients suspected of having CAI were divided into two groups according to sufficient (group 1) or insufficient (group 2) low-dose ACTH test serum cortisol response. Concordance with low (<2.5th percentile) or normal (≥2.5th percentile) basal serum DHEAS levels for age and sex, respectively, was analysed.

Results: Fifty patients (53.2%) in group 1 and 44 (46.8%) in group 2 were included. The median value of serum DHEAS levels in group 2 (0.7 µmol/l, interquartile range 0.44-1.49) was significantly lower than in group 1 (2.13 µmol/l, interquartile range 0.87-3.5; p < 0.03). Nevertheless, serum basal DHEAS levels as a diagnostic marker of CAI showed 39% sensitivity and 80% specificity.

Conclusion: In pubertal patients, basal serum DHEAS levels do not seem to be a useful tool to diagnose either sufficiency or insufficiency of secondary adrenal function.
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http://dx.doi.org/10.1159/000368318DOI Listing
July 2015