Quantification of Elastin Markers Synthesis in Williams-Beuren Syndrome and 7q11.23 Micro-duplication Syndrome

Plain-language summary

Introduction: Williams-Beuren syndrome is a rare genetic disorder caused by a 7q11.23 microdeletion. The phenotype associates vasculopathy (arterial stenosis, hypertension), dimorphism and intellectual disability. Microdeletion includes several genes: ELN encodes for elastin and the haplo-insufficiency (only 1 functional copy) causes vasculopathy. The primary objective is to quantify plasma and urinary levels of elastin peptides in Williams-Beuren patients and 7q11.23 micro-duplication syndrome patients in order to correlate the levels of these markers with the number of copies of ELN gene (proportional positive relationship "gene copy number - circulating levels of markers) Materials and Methods: This prospective study will be carried out in Lyon at the "Hôpital Femme-Mère-Enfant" for 2 years. 3 groups of patients will be studied: Williams-Beuren patients (N=20), micro-duplication 7q11.23 syndrome patients (N=10) and healthy patients (N=60). Subjects will be followed for 1 day. Clinical examination (weight, height, blood pressure) and biological sample collection (blood and urine sample) will be carry out for Williams Beuren and micro-duplication 7q11.23 patients group. A large majority of visits will be part of patients' usual care. A large part of patients are systematically seen in consultation once a year. For healthy group, only biological sample collection will be carry out. The PE concentrations will be assessed and compared between the three groups of patients.

Who can participate

What they're measuring

Trial details