Читать книгу Clinical Obesity in Adults and Children - Группа авторов - Страница 82

Up to 3% of patients with severe obesity have been found to harbor mutations in the leptin receptor gene (LEPR) that are associated with a loss of function in vitro [38]. Whilst heterozygosity for LEP or LEPR mutations is associated with an increase in body weight, severe obesity requires the loss of two alleles due to homozygous or compound heterozygous mutations. Serum leptin levels are not disproportionately elevated in LEPR deficiency, although particular mutations located near the transmembrane domain can result in a truncated extracellular domain that may act as a false binding protein and result in abnormally elevated leptin levels [39, 40]. The clinical phenotype of congenital leptin receptor deficiency is similar to that of leptin deficiency with hyperphagia, severe early‐onset obesity, hypogonadism, and frequent infections.