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Le Touquet – Paris-Plage, France

Nozieres C.,University of Lyon | Nozieres C.,Center Leon Berard | Zhang C.-X.,Center Leon Berard | Buffet A.,Service de Genetique | And 25 more authors.
Annales d'Endocrinologie | Year: 2014

Multiple Endocrine Neoplasia Type 1 (MEN1) is an autosomal dominant inherited syndrome, related to mutations in the MEN1 gene. Controversial data suggest that the nonsynonymous p.Ala541Thr variant, usually considered as a non-pathogenic polymorphism, may be associated with an increased risk of MEN1-related lesions in carriers. Objective: The aim of this study was to evaluate the pathogenic influence of the p.Ala541Thr variant on clinical and functional outcomes. Patients and methods: We analysed a series of 55 index patients carrying the p.Ala541Thr variant. Their clinical profile was compared to that of 117 MEN1 patients. The biological impact of the p.Ala541Thr variant on cell growth was additionally investigated on menin-deficient Leydig cell tumour (LCT)10 cells generated from Men1+/Men1- heterozygous knock-out mice, and compared with wild type (WT). Results: The mean age at first appearance of endocrine lesions was similar in both p.Ala541Thr carriers and MEN1 patients, but no p.Ala541Thr patient had more than one cardinal MEN1 lesion at initial diagnosis. A second MEN1 lesion was diagnosed in 13% of MEN1 patients and in 7% of p.Ala541Thr carriers in the year following preliminary diagnosis. Functional studies on LCT10 cells showed that overexpression of the p.Ala541Thr variant did not inhibit cell growth, which is in direct contrast to results obtained from investigation of WT menin protein. Conclusion: Taken together, these data raise the question of a potential pathogenicity of the p.Ala541Thr missense variant of menin that commonly occurs within the general population. Additional studies are required to investigate whether it may be involved in a low-penetrance MEN1 phenotype. © 2014 Elsevier Masson SAS.

Chen Y.-J.,Harbin Medical University | Yang Q.-H.,Harbin Medical University | Liu D.,Tongji University | Liu Q.-Q.,Tongji University | And 8 more authors.
European Journal of Clinical Investigation | Year: 2013

Background: Mutations in activin receptor-like kinase-1 (ACVRL-1) or endoglin (ENG) are mostly identified in patients with hereditary haemorrhagic telangiectasia (HHT) associated with pulmonary hypertension (PH), but have not yet been studied in Chinese patients. Material and methods: In this study, we investigated the clinical and molecular genetic features of Chinese patients with HHT-associated PH and analysed genotype/phenotype correlations in 14 probands and their relatives. Mutation analyses in ACVRL-1, bone morphogenetic protein receptor type 2 (BMPR2) and ENG were performed in 14 Chinese Han patients with HHT-associated PH. Results: The overall mutation rate was 71.4%, including 8 ACVRL-1 mutations and 2 ENG mutations, 6 of which were novel. Six patients were identified with arteriovenous malformations (AVMs), including four patients with pulmonary AVMs and two patients with liver AVMs. Five of the patients with AVMs were identified with mutations. Most patients received targeted therapy for PH. Conclusions: Our findings have revealed the clinical phenotype and molecular genetic features of HHT-associated PH in Chinese Han patients and indicate that mutations of ACVRL-1 and ENG are genetic predisposing factors in Chinese patients. Our data further addressed clinical management and have provided limited experience in treating this group of disorders. © 2013 Stichting European Society for Clinical Investigation Journal Foundation.

Linglart A.,Institute National Of La Santeet Of La Recherche Megdicale Unite 986 | Fryssira H.,Sophia Genetics | Hiort O.,Jugendmedizin Universitatsklinikum S | Holterhus P.-M.,Universitario Araba | And 22 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2012

Context: Acrodysostosis is a rare skeletal dysplasia that is associated with multiple resistance to G protein-coupled receptor (GPCR) signaling hormones in a subset of patients. Acrodysostosis is genetically heterogeneous because it results from heterozygous mutations in PRKAR1A or PDE4D, two key actors in the GPCR-cAMP-protein kinase A pathway. Objective: Our objective was to identify the phenotypic features that distinguish the two genotypes causing acrodysostosis. Patients and Methods: Sixteen unrelated patients with acrodysostosis underwent a candidategene approach and were investigated for phenotypic features. Results: All patients had heterozygous de novo mutations. Fourteen patients carried a PRKAR1A mutation (PRKAR1A patients), five each a novel PRKAR1A mutation (p.Q285R, p.G289E, p.A328V, p.R335L, or p.Q372X), nine the reported PRKAR1A p.R368X mutation; two patients harbored a mutation in PDE4D (PDE4D patients) (one novel mutation, p.A227S; one reported, p.E590A). All PRKAR1A, but none of the PDE4D mutated patients were resistant to PTH and TSH. Two PRKAR1A patients each with a novel mutation presented a specific pattern of brachydactyly. One PDE4D patient presented with acroskyphodysplasia. Additional phenotypic differences included mental retardation in PDE4D patients. In addition, we report the presence of pigmented skin lesions in PRKAR1A and PDE4D patients, a feature not yet described in the acrodysostosis entity. Conclusions: All PRKAR1A and PDE4D patients present similar bone dysplasia characterizing acrodysostosis. Phenotypic differences, including the presence of resistance to GPCR-cAMP signaling hormones in PRKAR1A but not PDE4D patients, indicate phenotype-genotype correlations and highlight the specific contributions of PRKAR1A and PDE4D in cAMP signaling in different tissues. Copyright © 2012 by The Endocrine Society.

Vasen H.F.A.,Leiden University | Moslein G.,St. Josefs Hospital Bochum Linden Helios | Alonso A.,Hospital Virgen del Camino | Aretz S.,University of Bonn | And 32 more authors.
Familial Cancer | Year: 2010

Familial colorectal cancer (CRC) accounts for 10-15% of all CRCs. In about 5% of all cases, CRC is associated with a highly penetrant dominant inherited syndrome. The most common inherited form of non-polyposis CRC is the Lynch syndrome which is responsible for about 2-4% of all cases. Surveillance of individuals at high risk for CRC prevents the development of advanced CRC. About 1 million individuals in Western Europe are at risk for Lynch syndrome. We performed a survey to evaluate the strategies currently used to identify individuals at high risk for CRC in 14 Western European countries. Questionnaires were distributed amongst members of a European collaborative group of experts that aims to improve the prognosis of families with hereditary CRC. The survey showed that in all countries obtaining a family history followed by referral to clinical genetics centres of suspected cases was the main strategy to identify familial and hereditary CRC. In five out of seven countries with a (regional or national) CRC population screening program, attention was paid in the program to the detection of familial CRC. In only one country were special campaigns organized to increase the awareness of familial CRC among the general population. In almost all countries, the family history is assessed when a patient visits a general practitioner or hospital. However, the quality of family history taking was felt to be rather poor. Microsatellite instability testing (MSI) or immunohistochemical analysis (IHC) of CRC are usually recommended as tools to select high-risk patients for genetic testing and are performed in most countries in patients suspected of Lynch syndrome. In one country, IHC was recommended in all new cases of CRC. In most countries there are no specific programs on cancer genetics in the teaching curriculum for medical doctors. In conclusion, the outcome of this survey and the discussions within an European expert group may be used to improve the strategies to identify individuals at high risk of CRC. More attention should be given to increasing the awareness of the general population of hereditary CRC. Immunohistochemical analysis or MSI-analysis of all CRCs may be an effective tool for identifying all Lynch syndrome families. The cost-effectiveness of this approach should be further evaluated. All countries with a CRC population screening program should obtain a full family history as part of patient assessment. ©Springer Science+Business Media B.V. 2009.

Thevenon J.,University of Burgundy | Bourredjem A.,French Institute of Health and Medical Research | Bourredjem A.,University of Burgundy | Faivre L.,University of Burgundy | And 44 more authors.
European Journal of Endocrinology | Year: 2015

Background: MEN1, which is secondary to the mutation of the MEN1 gene, is a rare autosomal-dominant disease that predisposes mutation carriers to endocrine tumors. Most studies demonstrated the absence of direct genotype-phenotype correlations. The existence of a higher risk of death in the Groupe d'étude des Tumeurs Endocrines-cohort associated with a mutation in the JunD interacting domain suggests heterogeneity across families in disease expressivity. This study aims to assess the existence of modifying genetic factors by estimating the intrafamilial correlations and heritability of the six main tumor types in MEN1. Methods: The study included 797 patients from 265 kindred and studied seven phenotypic criteria: parathyroid and pancreatic neuroendocrine tumors (NETs) and pituitary, adrenal, bronchial, and thymic (thNET) tumors and the presence of metastasis. Intrafamilial correlations and heritability estimates were calculated from family tree data using specific validated statistical analysis software. Results: Intrafamilial correlations were significant and decreased along parental degrees distance for pituitary, adrenal and thNETs. The heritability of these three tumor types was consistently strong and significant with 64% (S.E.M.Z0.13; P<0.001) for pituitary tumor, 65% (S.E.M.Z0.21; P<0.001) for adrenal tumors, and 97% (S.E.M.Z0.41; P=0.006) for thNETs. Conclusion: The present study shows the existence of modifying genetic factors for thymus, adrenal, and pituitary MEN1 tumor types. The identification of at-risk subgroups of individuals within cohorts is the first step toward personalization of care. Next generation sequencing on this subset of tumors will help identify the molecular basis of MEN1 variable genetic expressivity. © 2015 European Society of Endocrinology Printed in Great Britain.

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