A significantly higher proportion of patients with rare diseases (RD) with intellectual disability (ID), present hyperphagia, overweight or obesity, compared to the general population. Prader-Willi Syndrome (PWS) and related syndromes (PWS-like) represent the most well-known causes of eating disorders with early and severe obesity. Other known RD with ID have been described as being associated with eating disorders with overweight or obesity, which appear later in adolescence : Angelman's syndrome (approximately 40% of patients are overweight or obese, and 32% of children have hyperphagia), Fragile X syndrome (over 30% are obese), Smith-Magenis syndrome (50 to 60% are obese). Prader-Willi syndrome is the only genetic obesity identified to date associated with hyperghrelinemia, while ghrelin levels are lower than in controls in other situations of obesity.~The aim of the study is to find out whether the levels of ghrelin, which are abnormally high in PWS throughout life, are also high in these pathologies when people have hyperphagia and/or overweight.~The study involves a single visit carried out during a routine follow-up in the CRMR, in which the blood sample will allow the dosage of the ghrelin hormon. The visit will also involves a data collection and some questionnaires.
A significantly higher proportion of patients with rare diseases (RD) with intellectual disability (ID), present hyperphagia, overweight or obesity, compared to the general population. Prader-Willi syndrome is the only genetic obesity identified to date associated with hyperghrelinemia, while ghrelin levels are lower than in controls in other situations of obesity.~The aim of the study is to find out whether the levels of ghrelin, which are abnormally high in PWS throughout life, are also high in these RD when people have hyperphagia and/or overweight.