Houeijeh A.,Service de genetique clinique Guy Fontaine |
Andrieux J.,Laboratoire Of Genetique |
Saugier-Veber P.,University of Rouen |
David A.,Nantes University Hospital Center |
And 16 more authors.
European Journal of Medical Genetics | Year: 2011
Thrombocytopenia-absent radius Syndrome (TAR) is a rare congenital malformation syndrome of complicated transmission. 1q21.1 deletion is necessary but not sufficient for its expression. We report the result of a French multicentric clinical study, and we emphasized on the role of the associated 1q21.1 deletion in the diagnosis and the genetic counselling of our patients. We gathered information on 14 patients presenting with TAR syndrome and referred for genetic counselling in six different university hospitals (8 foetuses, 1 child and 5 adults). Clinical or pathology details, as well as skeletal X-rays were analyzed. Genetic studies were performed by Array-CGH, and Quantitative Multiplex PCR. We demonstrated the very variable phenotypes of TAR syndrome. Female:male ratio was ∼2:1. All patients presented with bilateral radial aplasia/hypoplasia with preserved thumbs. Phocomelia and lower limb anomalies were present in 28% of the cases. We reported the first case of cystic hygroma on affected foetus. 1q21.1 deletions ranging from 330 to 1100 kb were identified in all affected patients. Most of them were inherited from one healthy parent (80%). The identification of a 1q21.1 deletion allowed confirmation of TAR syndrome diagnosis, particularly in foetuses and in atypical phenotypes. Additionally, it allowed accurate genetic counselling, especially when it occurred de novo. These findings allowed discussing the diagnostic criteria and management towards TAR syndrome. © 2011 Elsevier Masson SAS. Source
Couve S.,Laboratoire Of Genetique Oncologique Of Lecole Pratique Des Hautes Etudes Ephe |
Couve S.,French Institute of Health and Medical Research |
Couve S.,Center Expert National Cancers Rares a |
Ladroue C.,Laboratoire Of Genetique Oncologique Of Lecole Pratique Des Hautes Etudes Ephe |
And 37 more authors.
Cancer Research | Year: 2014
The classic model of tumor suppression implies that malignant transformation requires full "two-hit" inactivation of a tumor-suppressor gene. However, more recent work in mice has led to the proposal of a "continuum" model that involves more fluid concepts such as gene dosage-sensitivity and tissue specificity. Mutations in the tumor-suppressor gene von Hippel-Lindau (VHL) are associated with a complex spectrum of conditions. Homozygotes or compound heterozygotes for the R200W germline mutation in VHL have Chuvash polycythemia, whereas heterozygous carriers are free of disease. Individuals with classic, heterozygous VHL mutations have VHL disease and are at high risk of multiple tumors (e.g., CNS hemangioblastomas, pheochromocytoma, and renal cell carcinoma). We report here an atypical family bearing two VHL gene mutations in cis (R200W and R161Q), together with phenotypic analysis, structural modeling, functional, and transcriptomic studies of these mutants in comparison with classical mutants involved in the different VHL phenotypes. We demonstrate that the complex pattern of disease manifestations observed in VHL syndrome is perfectly correlated with a gradient of VHL protein (pVHL) dysfunction in hypoxia signaling pathways. Thus, by studying naturally occurring familial mutations, our work validates in humans the "continuum" model of tumor suppression. © 2014 AACR. Source