Publications by authors named "Guglielmina Pepe"

51 Publications

Two-Dimensional Aortic Size Normalcy: A Novelty Detection Approach.

Diagnostics (Basel) 2021 Feb 2;11(2). Epub 2021 Feb 2.

Cardiology Service, CMSR Veneto Medica, 36077 Altavilla Vicentina, Italy.

To develop a tool for assessing normalcy of the thoracic aorta (TA) by echocardiography, based on either a linear regression model (Z-score), or a machine learning technique, namely one-class support vector machine (OC-SVM) (Q-score). TA diameters were measured in 1112 prospectively enrolled healthy subjects, aging 5 to 89 years. Considering sex, age and body surface area we developed two calculators based on the traditional Z-score and the novel Q-score. The calculators were compared in 198 adults with TA > 40 mm, and in 466 patients affected by either Marfan syndrome or bicuspid aortic valve (BAV). Q-score attained a better Area Under the Curve (0.989; 95% CI 0.984-0.993, sensitivity = 97.5%, specificity = 95.4%) than Z-score (0.955; 95% CI 0.942-0.967, sensitivity = 81.3%, specificity = 93.3%; < 0.0001) in patients with TA > 40 mm. The prevalence of TA dilatation in Marfan and BAV patients was higher as Z-score > 2 than as Q-score < 4% (73.4% vs. 50.09%, < 0.00001). Q-score is a novel tool for assessing TA normalcy based on a model requiring less assumptions about the distribution of the relevant variables. Notably, diameters do not need to depend linearly on anthropometric measurements. Additionally, Q-score can capture the joint distribution of these variables with all four diameters simultaneously, thus accounting for the overall aortic shape. This approach results in a lower rate of predicted TA abnormalcy in patients at risk of TA aneurysm. Further prognostic studies will be necessary for assessing the relative effectiveness of Q-score versus Z-score.
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http://dx.doi.org/10.3390/diagnostics11020220DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7912952PMC
February 2021

Sanger Validation of High-Throughput Sequencing in Genetic Diagnosis: Still the Best Practice?

Front Genet 2020 2;11:592588. Epub 2020 Dec 2.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

Next-generation sequencing (NGS)'s crucial role in supporting genetic diagnosis and personalized medicine leads to the definition of Guidelines for Diagnostic NGS by the European Society of Human Genetics. Factors of different nature producing false-positive/negative NGS data together with the paucity of internationally accepted guidelines providing specified NGS quality metrics to be followed for diagnostics purpose made the Sanger validation of NGS variants still mandatory. We reported the analysis of three cases of discrepancy between NGS and Sanger sequencing in a cohort of 218 patients. NGS was performed by Illumina MiSeq and Haloplex/SureSelect protocols targeting 97 or 57 or 10 gene panels usually applied for diagnostics. Variants called following guidelines suggested by the Broad Institute and identified according to MAF <0.01 and allele balance >0.2 were Sanger validated. Three out of 945 validated variants showed a discrepancy between NGS and Sanger. In all three cases, a deep evaluation of the discrepant gene variant results and methodological approach allowed to confirm the NGS datum. Allelic dropout (ADO) occurrence during polymerase chain or sequencing reaction was observed, mainly related to incorrect variant zygosity. Our study extends literature data in which almost 100% "high quality" NGS variants are confirmed by Sanger; moreover, it demonstrates that in case of discrepancy between a high-quality NGS variant and Sanger validation, NGS call should not be assumed to represent the source of the error. Actually, difficulties (i.e., ADO, unpredictable presence of private variants on primer-binding regions) of the so-called gold standard direct sequencing should be considered especially in light of the constantly implemented and accurate high-throughput technologies. Our data along with literature raise a discussion on the opportunity to establish a standardized quality threshold by International Guidelines for clinical NGS in order to limit Sanger confirmation to borderline conditions of variant quality parameters and verification of correct gene variant call/patient coupling on a different blood sample aliquot.
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http://dx.doi.org/10.3389/fgene.2020.592588DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7738558PMC
December 2020

When should a rare inherited connective tissue disorder be suspected in bicuspid aortic valve by primary-care internists and cardiologists? Proposal of a score.

Intern Emerg Med 2020 Sep 19. Epub 2020 Sep 19.

Cardiology Service, CMSR Veneto Medica, Altavilla Vicentina, Italy.

Size threshold for aortic surgery in bicuspid aortic valve (BAV) is debated. Connective tissue disorders (CTDs) are claimed as a clinical turning point, suggesting early surgery in BAV patients with CTD. Thus, we aimed at developing a score to detect high risk of carrying CTDs in consecutive BAVs from primary care. Ninety-eight BAVs without ectopia lentis or personal/family history of aortic dissection were studied at the Marfan syndrome Tuscany Referral Center. Findings were compared with those detected in 84 Marfan patients matched for sex and age. We selected traits with high statistical difference between MFS and BAV easily obtainable by cardiologists and primary-care internists: mitral valve prolapse, myopia ≥ 3DO, pectus carenatum, pes planus, wrist and thumb signs, and difference between aortic size at root and ascending aorta ≥ 4 mm. Clustering of ≥ 3 of these manifestations were more frequent in Marfan patients than in BAVs (71.4% vs 6.1%, p < 0.0001) resulting into an Odds Ratio to be affected by MFS of 38.3 (95% confidence intervals 14.8-99.3, p < 0.0001). We propose a score assembling simple clinical and echocardiographic variables resulting in an appropriate referral pattern of BAVs from a primary-care setting to a tertiary center to evaluate the presence of a potential, major CTD.
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http://dx.doi.org/10.1007/s11739-020-02458-1DOI Listing
September 2020

Clinical significance of family history and bicuspid aortic valve in children and young adult patients with Marfan syndrome.

Cardiol Young 2020 May 15;30(5):663-667. Epub 2020 Apr 15.

Inherited and Rare Cardiovascular Diseases, Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli", Monaldi Hospital, Naples, Italy.

Background: Marfan syndrome is an autosomal dominant disorder of the connective tissue, whose cardinal features affect eyes, musculoskeletal, and cardiovascular system. Despite prevalence and natural history of cardiovascular manifestation are well known in adults, little is known about children and young adult patients. The aim of this study was to describe a well-characterised cohort of consecutive children and young patients with marfan syndrome, looking at the impact of family history and presence of bicuspid aortic valve on disease severity.

Methods: A total of 30 consecutive children and young patients with Marfan syndrome were evaluated. All patients underwent a comprehensive clinical-instrumental-genetic evaluation. Particular attention was posed to identify differences in prevalence of cardiovascular abnormalities between patients with and without family history of Marfan syndrome or bicuspid aortic valve.

Results: Of these 30 patients, family history of Marfan syndrome and bicuspid aortic valve were present in 76 and 13%, respectively. Compared to patients with family history of Marfan syndrome, those without showed higher prevalence of aortic sinus dilation (87 versus 32%, p-value = 0.009), greater aortic sinus diameters (4.2 ± 2.1 versus 1.9 ± 1.1 z score, p-value = 0.002), and higher rate of aortic surgery during follow-up (37 versus 0%, p-value = 0.002). Compared to patients with tricuspid aortic valve, those with bicuspid aortic valve were younger (3.2 ± 4.3 versus 10.7 ± 6.8 years old, p-value = 0.043), showed greater aortic sinus diameters (4.2 ± 0.9 versus 2.2 ± 1.6 z score, p-value = 0.033), and underwent more frequently aortic root replacement (50 versus 4%, p-value = 0.004).

Conclusions: In our cohort of patients with Marfan syndrome, the absence of family history and the presence of bicuspid aortic valve were associated to severe aortic phenotype and worse prognosis.
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http://dx.doi.org/10.1017/S1047951120000748DOI Listing
May 2020

European reference network for rare vascular diseases (VASCERN) consensus statement for the screening and management of patients with pathogenic ACTA2 variants.

Orphanet J Rare Dis 2019 11 21;14(1):264. Epub 2019 Nov 21.

VASCERN HTAD European Reference Centre, Ghent, Belgium.

The ACTA2 gene encodes for smooth muscle specific α-actin, a critical component of the contractile apparatus of the vascular smooth muscle cell. Pathogenic variants in the ACTA2 gene are the most frequently encountered genetic cause of non-syndromic hereditary thoracic aortic disease (HTAD). Although thoracic aortic aneurysm and/or dissection is the main clinical manifestation, a variety of occlusive vascular disease and extravascular manifestations occur in ACTA2-related vasculopathy. Current data suggest possible mutation-specific manifestations of vascular and extra-aortic traits.Despite its relatively high prevalence, comprehensive recommendations on the care of patients and families with pathogenic variants in ACTA2 have not yet been established. We aimed to develop a consensus document to provide medical guidance for health care professionals involved in the diagnosis and treatment of patients and relatives with pathogenic variants in ACTA2.The HTAD Working Group of the European Reference Network for Rare Vascular Diseases (VASCERN) convened to review current literature and discuss expert opinions on clinical management of ACTA2 related vasculopathy. This consensus statement summarizes our recommendations on diagnosis, monitoring, treatment, pregnancy, genetic counselling and testing in patients with ACTA2-related vasculopathy. However, there is a clear need for additional prospective multicenter studies to further define proper guidelines.
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http://dx.doi.org/10.1186/s13023-019-1186-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6868850PMC
November 2019

Bicuspid Aortic Valve: Role of Multiple Gene Variants in Influencing the Clinical Phenotype.

Biomed Res Int 2018 5;2018:8386123. Epub 2018 Sep 5.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities, University of Florence, Italy.

Bicuspid aortic valve (BAV) is a common congenital heart defect with increased prevalence of aortic dilatation and dissection. BAV has an autosomal dominant pattern of inheritance with reduced penetrance and variable expressivity. BAV has been described as an isolated trait or associated with other clinical manifestations in syndromic conditions. Identification of a syndromic condition in a BAV patient is clinically relevant in order to personalize indication to aortic surgery. We aimed to point out how genetic diagnosis by next-generation sequencing (NGS) can improve management of a patient with complex BAV clinical picture. We describe a 45-year-old Caucasian male with BAV, thoracic aortic root and ascending aorta dilatation, and connective features evocative but inconclusive for clinical diagnosis of Marfan syndrome (MFS). Targeted (91 genes) NGS was used. Proband genetic variants were investigated in first-degree relatives. Proband carried 5 rare variants in 4 genes: (p.Asn542Ser and p.Lys2460Arg), (p.Val1739Met), (p.Arg1330Gln), and (p.Arg423Trp). The two FBN1 variants were inherited in cis by the mother, showing systemic features evocative of MFS, but with a milder phenotype than that observed in the proband. Careful clinical observation along with the presence of the variants allowed diagnosis of MFS in the proband and in his mother. variant was found in mother and brother, not exhibiting BAV, thus not definitely supporting/excluding association with BAV. Interestingly, the proband, his brother and father, all showing root dilatation, and his sister, with upper range aortic root dimension, were carriers of a variant. might also modulate the vascular phenotype. Our results underline the usefulness of NGS together with family evaluation in diagnosis of patients with monogenic traits and overlapping clinical manifestations due to contribution of the same genes and/or presence of comorbidities determined by different genes.
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http://dx.doi.org/10.1155/2018/8386123DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6145047PMC
January 2019

Role of lipoprotein (a) and LPA KIV2 repeat polymorphism in bicuspid aortic valve stenosis and calcification: a proof of concept study.

Intern Emerg Med 2019 Jan 11;14(1):45-50. Epub 2018 Aug 11.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities, University of Florence, Largo Brambilla 3, 50134, Florence, Italy.

Hemodynamic valvular impairment is a frequent determinant of the natural history of bicuspid aortic valve (BAV). The role of elevated Lp(a) levels and LPA Kringle IV type 2 (KIV-2) size polymorphism in influencing aortic valve calcification and stenosis development in patients with tricuspid aortic valve was recognized. In this study, we investigate the association between Lp(a) and LPA KIV-2 repeat number, and the presence of calcification and stenosis in BAV patients. Sixty-nine patients [79.7% males; median age 45(30-53) yrs], consecutively referred to Center for Cardiovascular Diagnosis or Referral Center for Marfan syndrome or related disorders, AOU Careggi, from June to November 2014, were investigated. For each patient, clinical (ECG and echocardiography) and laboratory [Lp(a) (Immunoturbidimetric assay) and LPA KIV-2 repeat number (real-time PCR)] evaluation were performed. Patients were compared with 69 control subjects. No significant association between Lp(a) circulating levels and LPA KIV-2 repeat number and BAV was evidenced. Among BAV patients, significantly higher Lp(a) levels according to calcification degree were found [no calcifications:78(42-159) mg/L, mild/moderate: 134(69-189) mg/L; severe: 560(286-1511) mg/L, p = 0.008]. Conversely, lower LPA KIV-2 repeat numbers in subjects with more severe calcification degree were observed. Furthermore, higher Lp(a) levels in patients with aortic stenosis [214(67-501) mg/L vs 104(56-169) mg/L, p = 0.043] were also found. In conclusion, present data suggest the potential role for Lp(a) as a possible risk marker useful to stratify, among BAV patients, those with a higher chance to develop valvular calcifications and aortic stenosis.
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http://dx.doi.org/10.1007/s11739-018-1925-8DOI Listing
January 2019

Genetic Bases of Bicuspid Aortic Valve: The Contribution of Traditional and High-Throughput Sequencing Approaches on Research and Diagnosis.

Front Physiol 2017 24;8:612. Epub 2017 Aug 24.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities, University of FlorenceFlorence, Italy.

Bicuspid aortic valve (BAV) is a common (0.5-2.0% of general population) congenital heart defect with increased prevalence of aortic dilatation and dissection. BAV has an autosomal dominant inheritance with reduced penetrance and variable expressivity. BAV has been described as an isolated trait or associated with syndromic conditions [e.g., Marfan Marfan syndrome or Loeys-Dietz syndrome (MFS, LDS)]. Identification of a syndromic condition in a BAV patient is clinically relevant to personalize aortic surgery indication. A 4-fold increase in BAV prevalence in a large cohort of unrelated MFS patients with respect to general population was reported, as well as in LDS patients (8-fold). It is also known that BAV is more frequent in patients with thoracic aortic aneurysm (TAA) related to mutations in , and genes. Moreover, in 8 patients with BAV and thoracic aortic dilation, not fulfilling the clinical criteria for MFS, mutations in 2/8 patients were identified suggesting that or other genes involved in syndromic conditions correlated to aortopathy could be involved in BAV. Beyond loci associated to syndromic disorders, studies in humans and animal models evidenced/suggested the role of further genes in non-syndromic BAV. The transcriptional regulator has been associated with the development and acceleration of calcium deposition. Genome wide marker-based linkage analysis demonstrated a linkage of BAV to loci on chromosomes 18, 5, and 13q. Recently, a role for / in aortic valve morphogenesis and endocardial cell differentiation has been reported. BAV has also been associated with a reduced gene expression or involvement of a locus containing /. Much remains to be understood about the genetics of BAV. In the last years, high-throughput sequencing technologies, allowing the analysis of large number of genes or entire exomes or genomes, progressively became available. The latter issue together with the development of "BigData" analysis methods improving their interpretation and integration with clinical data represents a promising opportunity to increase the disease knowledge and diagnosis in monogenic and multifactorial complex traits. This review summarized the main knowledge on the BAV genetic bases, the role of genetic diagnosis in BAV patient managements and the crucial challenges for the comprehension of genetics of BAV in research and diagnosis.
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http://dx.doi.org/10.3389/fphys.2017.00612DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5573733PMC
August 2017

Role of TGFBR1 and TGFBR2 genetic variants in Marfan syndrome.

J Vasc Surg 2018 07 26;68(1):225-233.e5. Epub 2017 Aug 26.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities, University of Florence, Florence, Italy; Marfan Syndrome and Related Disorders Regional (Tuscany) Referral Center, Careggi Hospital, Florence, Italy; Center of Excellence for the Study at Molecular and Clinical Level of Chronic, Degenerative and Neoplastic Diseases to Develop Novel Therapies, DENOTHE Center, University of Florence, Florence, Italy; Atherothrombotic Diseases Center, Careggi Hospital, Florence, Italy. Electronic address:

Objective: Genetic variants in transforming growth factor beta (TGF-β) receptors type 1 (TGFBR1) and type 2 (TGFBR2) genes have been associated with different hereditary connective tissue disorders sharing thoracic aortic aneurysm and dissection (TAA/D). Mutations in both TGFBR1/2 genes have been described in patients with TAA/D and Marfan syndrome (MFS), and they are associated consistently with Loeys-Dietz syndrome. The existing literature shows discordant data resulting from mutational screening of TGFBR1/2 genes in patients with MFS. The aim of the study was to investigate the role of TGFBR1/2 genetic variants in determining and/or modulating MFS clinical phenotype.

Methods: We investigated 75 unrelated patients with MFS referred to the Center for Marfan Syndrome and Related Disorders (Careggi University Hospital, Florence) who were subjected to FBN1 and TGFBR1/2 Sanger mutational screening.

Results: Forty-seven patients with MFS (63%) carried a pathogenetic FBN1 mutation. No pathogenetic mutations were detected in TGFBR1/2 genes. Ten common polymorphisms were identified in TGFBR2 and 6 in TGFBR1. Their association with cardiovascular manifestations was evaluated. Carriers of the A allele of rs11466512, delA allele of c.383delA or delT allele of c.1256-15del1T polymorphisms had a trend toward or significantly reduced z-scores (median [interquartile range (IQR)], 2.2 [1.13-4.77]; 2.1 [1.72-3.48]; 2.5 [1.85-3.86]) with respect to homozygous patients with wild-type MFS (median [IQR], 4.20 [2.39-7.25]; 3.9 [2.19-7.00]; 3.9 [2.14-6.93]). Carriers of the A allele of the rs2276767 polymorphism showed a trend toward increased z-score (median [IQR], 4.9 [2.14-7.16]) with respect to patients with wild-type MFS (median [IQR], 3.3 [1.75-5.45]). The protective effect of TGFBR1/2 genetic score including all the 4 variants was also evaluated. Patients with MFS with two or more protective alleles included in the score had statistically significant reduced aortic z-scores (median [IQR], 2.20 [1.48-3.37]) with respect to patients with 1 or no protective alleles (median [IQR], 4.20 [2.48-7.12]; P = .007). Patients with severe aortic manifestations (aortic z-score ≥ 2 or aortic surgery) showed a significantly lower prevalence of subjects with two or more protective alleles included in the genetic score (29.7%) than patients with no or milder cardiovascular involvement (63.6%; P = .029). The genetic score protective effect on global aortic manifestations severity (aortic z-score ≥ 2 or aortic surgery) was also observed at the logistic regression analysis adjusted for the presence of FBN1 gene mutations (odds ratio, 0.21; 95% CI, 0.05-0.84; P = .028).

Conclusions: In conclusion, our data reappraise the role of TGFBR1 and TGFBR2 as major genes in patients with MFS, and suggest that TGFBR1/2 genetic variants (in particular when evaluated as a burden by score) might play a role in modulating the severity of cardiovascular manifestation in MFS.
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http://dx.doi.org/10.1016/j.jvs.2017.04.071DOI Listing
July 2018

Fibrillins in Tendon.

Front Aging Neurosci 2016 20;8:237. Epub 2016 Oct 20.

Department of Experimental and Clinical Medicine, Excellence Centre for Research, Transfer and High Education for the Development of De Novo Therapies (DENOTHE), University of FlorenceFlorence, Italy; Marfan Syndrome and Related Disorders Regional (Tuscany) Referral Center, Careggi HospitalFlorence, Italy.

Tendons among connective tissue, mainly collagen, contain also elastic fibers (EF) made of fibrillin 1, fibrillin 2 and elastin that are broadly distributed in tendons and represent 1-2% of the dried mass of the tendon. Only in the last years, studies on structure and function of EF in tendons have been performed. Aim of this review is to revise data on the organization of EF in tendons, in particular fibrillin structure and function, and on the clinical manifestations associated to alterations of EF in tendons. Indeed, microfibrils may contribute to tendon mechanics; therefore, their alterations may cause joint hypermobility and contractures which have been found to be clinical features in patients with Marfan syndrome (MFS) and Beals syndrome. The two diseases are caused by mutations in genes FBN1 and FBN2 encoding fibrillin 1 and fibrillin 2, respectively.
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http://dx.doi.org/10.3389/fnagi.2016.00237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5071311PMC
October 2016

Another piece in the puzzle of bicuspid aortic valve syndrome.

Eur Heart J Cardiovasc Imaging 2016 11 7;17(11):1248-1249. Epub 2016 Aug 7.

Department of Radiology, Montreal Heart Institute, Universitè de Montreal, Montreal, Canada.

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http://dx.doi.org/10.1093/ehjci/jew169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5095692PMC
November 2016

A Case Based Approach to Clinical Genetics of Thoracic Aortic Aneurysm/Dissection.

Biomed Res Int 2016 25;2016:9579654. Epub 2016 May 25.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities, DENOTHE Center, University of Florence, Florence 50134, Italy; Department of Heart and Vessels, Marfan Syndrome and Related Disorders Regional Referral Center, Careggi Hospital, Florence 50134, Italy.

Thoracic aortic aneurysm/dissection (TAAD) is a potential lethal condition with a rising incidence. This condition may occur sporadically; nevertheless, it displays familial clustering in >20% of the cases. Family history confers a six- to twentyfold increased risk of TAAD and has to be considered in the identification and evaluation of patients needing an adequate clinical follow-up. Familial TAAD recognizes a number of potential etiologies with a significant genetic heterogeneity, in either syndromic or nonsyndromic forms of the manifestation. The clinical impact and the management of patients with TAAD differ according to the syndromic and nonsyndromic forms of the manifestation. The clinical management of TAAD patients varies, depending on the different forms. Starting from the description of patient history, in this paper, we summarized the state of the art concerning assessment of clinical/genetic profile and therapeutic management of TAAD patients.
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http://dx.doi.org/10.1155/2016/9579654DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4897665PMC
February 2017

Marfan syndrome: current perspectives.

Appl Clin Genet 2016 9;9:55-65. Epub 2016 May 9.

Cardiothoracovascular Department, Marfan Syndrome and Related Disorders Regional Referral Center, Careggi Hospital, Florence, Italy; Cardiology Service, CMSR Veneto Medica, Altavilla Vicentina, Italy.

Marfan syndrome (MFS) is a pleiotropic connective tissue disease inherited as an autosomal dominant trait, due to mutations in the FBN1 gene encoding fibrillin 1. It is an important protein of the extracellular matrix that contributes to the final structure of a microfibril. Few cases displaying an autosomal recessive transmission are reported in the world. The FBN1 gene, which is made of 66 exons, is located on chromosome 15q21.1. This review, after an introduction on the clinical manifestations that leads to the diagnosis of MFS, focuses on cardiovascular manifestations, pharmacological and surgical therapies of thoracic aortic aneurysm and/or dissection (TAAD), mechanisms underlying the progression of aneurysm or of acute dissection, and biomarkers associated with progression of TAADs. A Dutch group compared treatment with losartan, an angiotensin II receptor-1 blocker, vs no other additional treatment (COMPARE clinical trial). They observed that losartan reduces the aortic dilatation rate in patients with Marfan syndrome. Later on, they also reported that losartan exerts a beneficial effect on patients with Marfan syndrome carrying an FBN1 mutation that causes haploinsufficiency (quantitative mutation), while it has no significant effect on patients displaying dominant negative (qualitative) mutations. Moreover, a French group in a 3-year trial compared the administration of losartan vs placebo in patients with Marfan syndrome under treatment with beta-receptor blockers. They observed that losartan decreases blood pressure but has no effect on aortic diameter progression. Thus, beta-receptor blockers remain the gold standard therapy in patients with Marfan syndrome. Three potential biochemical markers are mentioned in this review: total homocysteine, serum transforming growth factor beta, and lysyl oxidase. Moreover, markers of oxidative stress measured in plasma, previously correlated with clinical features of Marfan syndrome, may be explored as potential biomarkers of clinical severity.
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http://dx.doi.org/10.2147/TACG.S96233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4869846PMC
June 2016

A group of patients with Marfan's syndrome, who have finger and toe contractures, displays tendons' alterations upon an ultrasound examination: are these features common among classical Marfan patients?

Intern Emerg Med 2016 Aug 22;11(5):703-11. Epub 2016 Feb 22.

Department of Heart and Vessels, Regional Marfan Syndrome and Related Disorders Center, Careggi Hospital, Florence, Italy.

The involvement of the musculoskeletal system with other mild pleiotropic manifestations represents a clinical criterion, called "systemic features," to d iagnose Marfan's syndrome. We aimed to investigate the features of the hands and feet redressable contractures present in a group of Marfan patients. In 13 patients with previously diagnosed Marfan's syndrome, an accurate clinical examination was performed. In particular the characterization of the musculoskeletal system by visual analogic scale to measure muscle pain (VAS) and muscle strength (MRC system) was carried out; the Beighton scale score was used to evaluate the articular hypermobility. Ultrasound examination (US) was performed to detect deep-superficial flexor tendons and extensor tendons of both hands, and the short and long flexor and extensor tendons of the fingers and toes in static and dynamic positions. The ImageJ program was adopted to measure a profile of tendon echo-intensity. A reduction of the thickness of all tendons was detected by US in our patients; the VAS and Beighton scale scores were in normal ranges. The profile of tendon echo-intensity showed different textural details in all Marfan patients. This study provides evidence for other contractures' localization, and for altered findings of the tendons in patients with Marfan syndrome and finger/toe contractures. These changes may be associated with structural modifications in connective tissue.
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http://dx.doi.org/10.1007/s11739-016-1399-5DOI Listing
August 2016

[Paradigm shifts in aortic pathology: clinical and therapeutic implications. Clinical imaging in chronic and acute aortic syndromes. The aorta as a cause of cardiac disease].

G Ital Cardiol (Rome) 2014 Jun;15(6):363-75

Multimodal imaging plays a pivotal role in the assessment of the thoracic aorta, both in chronic and acute settings. Moving from improved knowledge on the structure and function of the aortic wall, as well as on its pathophysiology and histopathology, appropriate utilization of each imaging modality results into a better definition of the patient's need and proper treatment strategy. This review is aimed at highlighting the most critical aspects in this field, providing cardiologists with some novel clues for the imaging approach to patients with thoracic aortic disease.
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http://dx.doi.org/10.1714/1582.17280DOI Listing
June 2014

Identification of fibrillin 1 gene mutations in patients with bicuspid aortic valve (BAV) without Marfan syndrome.

BMC Med Genet 2014 Feb 24;15:23. Epub 2014 Feb 24.

Department of Experimental and Clinical Medicine, Section of Critical Medical Care and Medical Specialities; DENOTHE Center, University of Florence, Largo Brambilla 3, 50134 Florence, Italy.

Background: Bicuspid aortic valve (BAV) is the most frequent congenital heart disease with frequent involvement in thoracic aortic dilatation, aneurysm and dissection. Although BAV and Marfan syndrome (MFS) share some clinical features, and some MFS patients with BAV display mutations in FBN1, the gene encoding fibrillin-1, the genetic background of isolated BAV is poorly defined.

Methods: Ten consecutive BAV patients [8 men, age range 24-42 years] without MFS were clinically characterized. BAV phenotype and function, together with evaluation of aortic morphology, were comprehensively assessed by Doppler echocardiography. Direct sequencing of each FBN1 exon with flanking intron sequences was performed on eight patients.

Results: We detected three FBN1 mutations in two patients (aged 24 and 25 years) displaying aortic root aneurysm ≥50 mm and moderate aortic regurgitation. In particular, one patient had two mutations (p.Arg2726Trp and p.Arg636Gly) one of which has been previously associated with variable Marfanoid phenotypes. The other patient showed a pArg529Gln substitution reported to be associated with an incomplete MFS phenotype.

Conclusions: The present findings enlarge the clinical spectrum of isolated BAV to include patients with BAV without MFS who have involvement of FBN1 gene. These results underscore the importance of accurate phenotyping of BAV aortopathy and of clinical characterization of BAV patients, including investigation of systemic connective tissue manifestations and genetic testing.
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http://dx.doi.org/10.1186/1471-2350-15-23DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3937520PMC
February 2014

Rheumatoid arthritis.

Autoimmune Dis 2013 28;2013:958437. Epub 2013 Nov 28.

Infectious Diseases Unit, University of Bologna, Bologna, Italy.

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http://dx.doi.org/10.1155/2013/958437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3863497PMC
December 2013

Dural ectasia and FBN1 mutation screening of 40 patients with Marfan syndrome and related disorders: role of dural ectasia for the diagnosis.

Eur J Med Genet 2013 Jul 15;56(7):356-60. Epub 2013 May 15.

Department of Medical and Surgical Critical Care, University of Florence, Viale Morgagni 85, 50134 Florence, Italy.

Marfan syndrome is an autosomal dominant disorder of connective tissue caused by mutations in the gene encoding fibrillin-1 (FBN1), a matrix component of microfibrils. Dural ectasia, i.e. enlargement of the neural canal mainly located in the lower lumbar and sacral region, frequently occurs in Marfan patients. The aim of our study was to investigate the role of dural ectasia in raising the diagnosis of Marfan syndrome and its association with FBN1 mutations. We studied 40 unrelated patients suspected for MFS, who underwent magnetic resonance imaging searching for dural ectasia. In all of them FBN1 gene analysis was also performed. Thirty-seven patients resulted affected by Marfan syndrome according to the '96 Ghent criteria; in 30 of them the diagnosis was confirmed when revaluated by the recently revised criteria (2010). Thirty-six patients resulted positive for dural ectasia. The degree of dural ectasia was grade 1 in 19 patients, grade 2 in 11 patients, and grade 3 in 6 patients. In 7 (24%) patients, the presence of dural ectasia allowed to reach a positive score for systemic feature criterion. Twenty-four patients carried an FBN1 mutation, that were represented by 13 missense (54%), and 11 (46%) mutations generating a premature termination codon (PTC, frameshifts and stop codons). No mutation was detected in the remaining 16 (6 patients with MFS and 10 with related disorders according to revised Ghent criteria). The prevalence of severe (grade 2 and grade 3) involvement of dura mater was higher in patients harbouring premature termination codon (PTC) mutations than those carrying missense-mutations (8/11 vs 2/13, P = 0.0111). Our data emphasizes the importance of dural ectasia screening to reach the diagnosis of Marfan syndrome especially when it is uncertain and indicates an association between PTC mutations and severe dural ectasia in Marfan patients.
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http://dx.doi.org/10.1016/j.ejmg.2013.04.006DOI Listing
July 2013

[Paradigm shifts in aortic pathology: clinical and therapeutic implications. Biology and pathology of the aortic wall].

G Ital Cardiol (Rome) 2013 Feb;14(2):97-109

Dipartimento di Scienze Radiologiche, Sapienza Universita di Roma, Italy.

Improved knowledge of the structure and function of the aortic wall, as well as its pathophysiology and histopathology, will result in an increasing impact on clinical evaluation and treatment of thoracic aortic diseases. This opinion paper highlights the main "paradigmatic shifts" in this field, providing cardiologists with some novel clues for the clinical approach to patients with thoracic aortic disease.
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http://dx.doi.org/10.1714/1218.13522DOI Listing
February 2013

Pectus excavatum and MASS phenotype: an unknown association.

J Laparoendosc Adv Surg Tech A 2012 Jun 8;22(5):508-13. Epub 2012 May 8.

Department of Pediatric Surgery, Children's Hospital A Meyer, Florence, Italy.

Introduction: Severe pectus excavatum (PE) is a deep chest wall deformity that generates both a cosmetic damage and a cardiac/respiratory function impairment. Excluding the scarce reports on Marfan's syndrome (MFS) and Ehlers-Danlos's syndrome (EDS), few studies have examined the relation between severe PE and connective tissue disorders. The aim of this study is to verify the clinical significance of such correlation.

Subjects And Methods: Ninety-two consecutive patients, of whom 79 were males, between 6 and 34 years old, classified as having severe PE, were seen at our institution from June 2005 to September 2010. All patients underwent clinical, ophthalmological, cardiac, and radiological (chest and spine magnetic resonance imaging) screening. The following features were observed: skin stretch marks, scoliosis, joint hypermobility, echocardiographic signs, spinal defects, and myopia.

Results: Classical connectivopathies such as MFS or EDS were present in only 5 patients (approximately 5%), whereas a single deformity was present in 4. The largest group (approximately 71%) was represented by phenotypical alterations such as mitral valve prolapse, aortic root enlargement, and skeletal and skin alterations (MASS). Among those patients, the most frequent clinical manifestations were the skeletal ones, followed by skin marks and mitral valve prolapse.

Conclusions: PE showed an evident association with an array of features that we describe as MASS. Although not one of this subgroup of patients has been described with increased aortic root diameter when screened (a feature widely present in MFS patients), they probably would require a thorough and longer follow-up than those affected by isolated PE because of the potential occurrence of severe cardiovascular complications such as aneurysms and dissection, which are major causes of morbidity and mortality in MFS.
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http://dx.doi.org/10.1089/lap.2012.0009DOI Listing
June 2012

Fibroblast autofluorescence in connective tissue disorders: a future tool for clinical and differential diagnosis?

J Biomed Opt 2008 Sep-Oct;13(5):054025

University of Florence, Department of Clinical Physiopathology, ASAcampus, ASA Research Division, Florence, Italy.

Marfan syndrome (MFS) is an inherited disorder of connective tissue due to mutations in FBN1 (90%) and TGFBR1 and TGFBR2 (5 to 10%) genes. Clinical and differential diagnosis is difficult because of the inter- and intrafamiliar marked heterogeneity and the variable onset age of clinical manifestations. Among the disorders, in differential diagnosis, thoracic aortic aneurysm (TAA) and Ullrich scleroatonic muscular dystrophy (UCMD) are reported. We evaluate the possibility of utilizing autofluorescence (AF) analysis as a diagnostic tool in the clinical and/or differential diagnosis of MFS and related disorders and in the investigation of the molecular mechanisms involved. Both multispectral imaging autofluorescence microscopy (MIAM) and autofluorescence microspectroscopy (AMS) have been used to characterize AF emission of fibroblasts from patients affected by inherited connective tissue disorders. Our preliminary results show significant differences in AF emission between normal and pathological fibroblasts, suggesting possible improvement in diagnostics of connective tissue disorders by AF analysis.
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http://dx.doi.org/10.1117/1.2982533DOI Listing
February 2009

Growth hormone (GH1) gene variation and the growth hormone receptor (GHR) exon 3 deletion polymorphism in a West-African population.

Mol Cell Endocrinol 2008 Dec 4;296(1-2):18-25. Epub 2008 Oct 4.

Institute of Medical Genetics, School of Medicine, Cardiff University, Heath Park, Cardiff, UK.

Among Europeans, functionally significant GH1 gene variants occur not only in individuals with idiopathic growth hormone (GH) deficiency and/or short stature but also fairly frequently in the general population. To assess the generality of these findings, 163 individuals from Benin, West Africa were screened for mutations and polymorphisms in their GH1 genes. A total of 37 different sequence variants were identified in the GH1 gene region, 24 of which occurred with a frequency of >1%. Although four of these variants were novel missense substitutions (Ala13Val, Arg19His, Phe25Tyr and Ser95Arg), none of these had any measurable effect on either GH function or secretion in vitro. Some 37 different GH1 promoter haplotypes were identified, 23 of which are as yet unreported in Europeans. The mean in vitro expression level of the GH1 promoter haplotypes observed in the African population was significantly higher than that previously measured in Britons (p<0.001). A gene conversion in the GH1 promoter, previously reported in a single individual of British origin, was found to occur at polymorphic frequency (5%) in the West-African population and was associated with a 1.7-fold increase in promoter activity relative to the wild-type. The d3 allele of the GHR exon 3 deletion polymorphism, known to be associated with increased GH responsiveness, was also found to occur at an elevated frequency in these individuals from Benin. We speculate that both elevated GH1 gene expression and increased GHR-mediated GH responsiveness may constitute adaptive responses to the effects of scarce food supply in this West-African population since increased circulating GH appears to form part of a physiological response to nutritional deprivation.
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http://dx.doi.org/10.1016/j.mce.2008.09.023DOI Listing
December 2008

A gene conversion hotspot in the human growth hormone (GH1) gene promoter.

Hum Mutat 2009 Feb;30(2):239-47

Institut für Medizinische Informatik und Statistik, Christian-Albrechts-Universität Kiel, Kiel, Germany.

To assess the evolutionary importance of nonallelic (or interlocus) gene conversion for the highly polymorphic human growth hormone (GH1) gene promoter, sequence variation in this region was studied in four different ethnic groups. For 14 SNPs in the proximal GH1 promoter (535 bp), 60 different haplotypes were observed in 577 individuals (156 Britons, 116 Spaniards, 163 West-Africans, 142 Asians). Using a novel coalescence-based statistical test, significant evidence was found in the British, Spanish, and African groups for GH1 having acted as an acceptor of gene conversion, with at least one of the four paralogous GH gene promoters serving as the donor (and specifically GH2 in the Britons and Spaniards). The average gene conversion tract length was estimated to be 84 bp. A gene conversion hotspot was identified, spanning the GH1 transcriptional initiation site (positions -6 to +25). Although these findings serve to highlight the importance of gene conversion for the recent evolution of the human GH1 promoter, its relative frequency does not appear to be related simply to the presence of specific DNA sequence motifs or secondary structures, the degree of homology between GH paralogs, the distance between them, or their transcriptional orientation. The GH1 promoter was also found to be highly polymorphic in chimpanzee but not in macaque. This may reflect the lower degree of pair-wise similarity between the GH1 promoter and its paralogs in macaque (mean, 92.0%) as compared to chimpanzee (93.5%) and human (94.0%), and hence provides further support for the idea of a threshold (perhaps around 92%) below which gene conversion is reduced or abolished.
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http://dx.doi.org/10.1002/humu.20850DOI Listing
February 2009

ACE and TGFBR1 genes interact in influencing the susceptibility to abdominal aortic aneurysm.

Atherosclerosis 2009 Jan 29;202(1):205-10. Epub 2008 Apr 29.

Department of Medical and Surgical Critical Care, University of Florence, Thrombosis Centre, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.

A role of ACE I/D polymorphism in the pathogenesis of abdominal aortic aneurysm (AAA) has been demonstrated, possibly due to the effect of angiotensin II on vascular tissue remodelling. Angiotensin II exerts profibrogenic effects through the local induction of TGF-beta. Dysregulated TGF-beta signalling may result from mutations in TGFBR1 and TGFBR2 genes, thus resulting in degenerative changes in the vessel wall. We performed a case-control study in order to investigate the role of TGFBR1 9A6A polymorphism as predisposing factor to AAA per se, and in the presence of ACE DD and AT1R 1166 CC genotypes in 201 AAA patients (mean age+/-S.D., 71.5+/-6.9) referred to the Unit of Vascular Surgery of the University of Florence, compared with 252 healthy controls (mean age+/-S.D., 70.6+/-8.6). A significant difference in genotype distribution and allele frequency between patients and controls was found for ACE, but not for AT1R and TGFBR1 polymorphisms. At univariate analysis a significant association between ACE DD, but not AT1R CC and TGFBR1 6A allele, and the susceptibility to the disease was found [ACE DD OR=1.86 (95% CI 1.26-2.76), p=0.002]. After adjustment for age, gender, traditional cardiovascular risk factors, and CAD, PAD and CVD, ACE DD genotype still affected the susceptibility to AAA [OR=2.13 (95% CI 1.06-4.28), p=0.03], and the contemporary presence of ACE DD genotype and TGFBR1 6A allele, increased the predisposition to the disease [OR=5.09 (95% CI 1.44-18.02), p=0.01]. This study, which demonstrates an interaction between ACE and TGFBR1 genes in predisposing to AAA, may provide further information on the mechanisms contributing to AAA susceptibility, and offer a topic for future larger studies.
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http://dx.doi.org/10.1016/j.atherosclerosis.2008.04.038DOI Listing
January 2009

Vascular and connective tissue features in 5 Italian patients with homocystinuria.

Int J Cardiol 2009 May 15;134(2):251-4. Epub 2008 Feb 15.

Homocystinuria is a metabolic disorder associated with defects in genes encoding for methionine metabolism enzymes. Vascular and connective tissue manifestations such as deep venous thrombosis, ectopia lentis and skeletal alterations are the major clinical features. We investigated the clinical manifestations of 5 Italian homocystinuric patients, performed mutation screening analysis on cystationine beta-synthase (CBS) gene and searched for genotype/phenotype correlations. We detected mild cardiovascular and skin connective tissue stigmas in these patients, never reported in homocystinuric patients before. We found 1 novel and 7 known mutations. Our patients carried no other mutation associated with venous thrombosis. Our data stress the importance of extending the clinical investigation for connective tissue manifestations in homocystinuric patients to all the organs/systems involved in Marfan syndrome, also suggesting long term follow-ups for cardiovascular manifestations.
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http://dx.doi.org/10.1016/j.ijcard.2007.12.029DOI Listing
May 2009

Is ectopia lentis in some cases a mild phenotypic expression of Marfan syndrome? Need for a long-term follow-up.

Mol Vis 2007 Nov 29;13:2242-7. Epub 2007 Nov 29.

Department of Medical and Surgical Critical Care, University of Florence, Regional Marfan Centre, Florence, Centre of Research, Transfer, High Education 'DENOTHE', University of Florence, Italy.

Purpose: Ectopia lentis (EL) and Marfan syndrome (MFS) are considered two distinct clinical entities. We performed genetic and clinical studies to investigate whether EL is actually distinct from MFS or if it is a mild phenotypic expression of it.

Methods: Seven patients with EL were followed for 5-10 years. Mutation screening analysis of the 65 exons of FBN1 was performed by polymerase chain reaction (PCR) amplification of genomic DNA, denaturing high pressure liquid chromatography analysis, and direct sequencing of heteroduplexes.

Results: Yearly examinations during the 10 years of follow-up allowed the detection of a late onset of dural ectasia in six out of seven patients (age range: 32-64 years versus 8-55 years in MFS previously reported). We also detected the onset of mild thoracic aortic dilatation in a sporadic case (age 45). Six out of seven index cases of EL turned out to be mild forms of Marfan syndrome with possible late cardiovascular involvement as detected in one case. Four novel missense mutations and one known splicing mutation were detected in five out of seven (71%) patients. Their localization confirmed the presence of a first hot spot within exons 1-15 and suggested the presence of a second one between exons 31-39.

Conclusions: The presence of a second major criterion in six EL patients shifted the clinical diagnosis from EL to MFS. These data demonstrate that some cases, which are initially diagnosed as EL, turn out to be mild Marfan patients. A clinical cardiovascular follow-up is therefore highly recommended for all EL patients since they may develop thoracic aortic aneurysm (TAA) or dissection later in life. Also magnetic resonance imaging (MRI) for dural ectasia (DE) should be performed in a complete follow up for a MFS diagnosis.
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November 2007

May TGFBR1 act also as low penetrance allele in Marfan syndrome?

Int J Cardiol 2009 Jan 22;131(2):281-4. Epub 2007 Oct 22.

Marfan syndrome, a human disease involving cardiovascular and skeletal apparatuses and ocular and central nervous systems, is associated to mutations in FBN1 gene; heterozygous mutations in TGFBR2 and TGFBR1 genes were found associated to MFS type 2, characterized by the presence of skeletal and cardiovascular major criteria and absence of eye major criterion. We screened the TGFBR1 gene in 46 Marfan patients in whom mutations in FBN1 and TGFBR2 genes were excluded and the analysis of Ex1 was extended to additional 114 Marfan patients and 237 controls. We detected two potentially pathological sequence variants: the TGFBR1 6Ala allele whose frequency was higher in the group of Marfan patients (0.13) than in the controls (0.08) (p=0.013; OR=1.69) and an insertion of 20 nucleotides in the 5'UTR that turned out to be a familial silent rare polymorphism. We hypothesize that TGFBR1 sequence variants may act not only as major, but also as low penetrance alleles of the clinical phenotype in Marfan syndrome.
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http://dx.doi.org/10.1016/j.ijcard.2007.07.048DOI Listing
January 2009

Polymorphisms of the COL1A2, CYP1A1 and HS1,2 Ig enhancer genes in the Tuaregs from Libya.

Ann Hum Biol 2007 Jul-Aug;34(4):425-36

University of Rome Tor Vergata, Rome, Italy.

Background: Restriction fragment length polymorphisms (RFLPs) of the COL1A2 and CYP1A1 and short tandem repeats of HS1,2 Ig enhancer genes are proving to be useful markers for describing human populations and thus are of interest for anthropogenetic research. Moreover, they can provide useful information in identifying alleles and haplotypes associated with particular forms of common diseases or for pharmacogenomics studies.

Aim: The objective of this study was to define the genetic structure of Libyan Tuaregs and to establish the degree of genetic homogeneity amongst the El Awaynat and Tahala groups.

Subjects And Methods: Tuareg individuals from El Awaynat (n = 99) and Tahala (n = 18), in Libyan Sahara, were analysed for the RFLPs of COL1A2 and CYP1A1 and short tandem repeats of HS1,2 Ig enhancer genes. In order to provide a clearer picture of COL1A2, CYP1A1 and HS1,2 Ig enhancer allele and haplotype frequency distributions in various human groups distributed over a wide geographic area, comparisons with other African, European and Asian populations were carried out by analysis of molecular variance (AMOVA) and genetic distance analysis.

Results: No significant level of differentiation was evident between the two Libyan Tuareg groups according to AMOVA. For the CYP1A1 gene, a possible new haplotype was observed, even though at a very low frequency. Linkage disequilibrium was assessed only for COL1A2, since CYP1A1 turned out to be poorly polymorphic for m2 and m3.

Conclusions: Statistical analyses showed that Tuaregs from Libya are located in a intermediate position between south Saharan populations on one side and the Europeans and the Asians on the other.
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http://dx.doi.org/10.1080/03014460701362356DOI Listing
September 2007

Ullrich myopathy phenotype with secondary ColVI defect identified by confocal imaging and electron microscopy analysis.

Neuromuscul Disord 2007 Aug 27;17(8):587-96. Epub 2007 Jun 27.

Unit of Molecular Medicine, Department of Laboratory Medicine, Bambino Gesù Paediatric Hospital IRCCS, Piazza S. Onofrio 4, 00165 Rome, Italy.

Ullrich congenital muscular dystrophy (UCMD) is clinically characterized by muscle weakness, proximal contractures and distal hyperlaxity and morphologically branded by absence or reduction of collagen VI (ColVI), in muscle and in cultured fibroblasts. The ColVI defect is generally related to COL6 genes mutations, however UCDM patients without COL6 mutations have been recently reported, suggesting genetic heterogeneity. We report comparative morphological findings between a UCMD patient harboring a homozygous COL6A2 mutation and a patient with a typical UCMD phenotype in which mutations in COL6 genes were excluded. The patient with no mutations in COL6 genes exhibited a partial ColVI defect, which was only detected close to the basal membrane of myofibers. We describe how confocal microscopy and rotary-shadowing electron microscopy may be useful to identify a secondary ColVI defect.
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http://dx.doi.org/10.1016/j.nmd.2007.04.010DOI Listing
August 2007