Background: Polymorphic genes Val158Met gene catechol-O-metiltrasferaz (COMT) are used to be responsible for less neurotransmitters utilization.
Objective and hypotheses: To determine the peculiarities of neurotransmitters levels in children with obesity and different genotypes of COMT gene.
Method: We examined 191 pubertal obese children. Patients were divided: Group1 (simple obesity) 143 children, 14.3±1.8 years, 30.6±2.8 kg/m2; group2 (severe obesity) 48 children, 15.2±1.8 years (P=0.3), 39.7±4.2 kg/m2 (P=0.0001). Control 80 children, 14.4±2 years (P=0.5), 14.4±2 kg/m2 (P=0.0001). Dopamine, serotonin levels were determined. Genotyping was performed on polymorphic genes COMT. Statistical analyse was using SPSS.18.
Results: We determined more frequent occurrence of GA (Val/Met) genotype COMT gene in children with severe obesity (54.3%) compared to simple disease (32.7%) (χ2=6.9; P=0.03). AA genotype frequency was 21.7% in patients with severe obesity, 45.5% and simple one which were higher than control (16.6%) (χ2=14.6; P=0.006). We revealed significantly higher BMI in children with severe obesity and the presence of GA genotype (41.3±4.5 kg/m2) compared to GG (37.4±3.1) (P=0.006) and AA (38.6±2.8) (P=0.04) genotypes. We did not find any significant differences in BMI values between children with simple obesity and GG, GA, AA genotypes. A statistically significant difference between dopamine levels were in patients with simple (8.8(4.8; 20.7)) and severe obesity (48.8(29.8, 163.9)) ng/ml and AA genotype (P=0.05). We found a significant increase in serotonin levels in patients with severe obesity and the presence of GA (P=0.02) and AA (P=0.01) genotypes compared with GG. There were no significant differences in the concentration of serotonin in children with simple obesity with different genotypes.
Conclusion: A large frequency of AA genotype were found in children with severe and simple obesity. Higher BMI levels were in children with severe obesity and genotype GA. A significant serotonin increasing levels were in patients with severe obesity and the presence of GA and AA genotypes.
10 - 12 Sep 2016
European Society for Paediatric Endocrinology