Background: Melanocortin-4 receptor (MC4R) mutations are the most common known cause of monogenic obesity but there is no data for Turkish children.
Objective: To determine the prevalence of MC4R mutations in a group of Turkish morbid obese children and adolescents.
Method: MC4R gene was sequenced in 47 consecutive morbidly obese children and adolescents (28 girls and 19 boys, aged 118 years) who presented during a 1-year period. Inclusion criterion was a BMI ≥120 percent of the 95th percentile or ≥35 kg/m2. Those with chronic diseases, Cushing syndrome, hypothyroidism, or suspected syndromes that could cause obesity were excluded. Onset of obesity was before the 10th year of life in all subjects.
Results: Mean values of age of all patients was 13.2±4.1 years, age at onset of obesity 5.1±2.1 years, height SD score 1.21±0.93, BMI 40.0±8.8, BMI SD score 2.72±0.37. One novel (c.870delG) and two previously reported (c.496 G>A, c.346_347delAG) mutations have been found in four (8.5%) obese children and adolescents. The novel mutation (c.870delG) was predicted to be a disease-causing frame-shift mutation using in silico analyses. Fasting glucose and lipid levels of the patients with MC4R mutation were normal but insulin resistance was present in two of them. Six more individuals with MC4R mutation (one child, five adults) were detected following analyses of the family members of affected children.
Conclusion: This study is the first to report the prevalence of Turkish children and adolescents with morbid obesity. MC4R gene mutations are frequently found in morbid obese Turkish children and adolescents as well.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology