ESPE Abstracts

Background: Serotonine transporter gene (SLC6A4) polymorphism is one of genetic aspects of appetite and mood disorders.

Objective and hypotheses: To determine the frequencies of 5-HTTLPR locus in promotor part of serotonine transporter gene (SLC6A4) polymorphism in children with different forms of obesity.

Method: We examined 191 pubertal obese children. Patients were divided: Group 1 (simple obesity) 143 children, 14.3±1.8 years, 30.6±2.8 kg/m²; group 2 (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). Serotonin levels, genotyping on 5-HTTLPR locus in serotonine transporter gene (SLC6A4)) promotor part were determined. Psychological testing using DSRS scales were used. Statistics was performed using SPSS.18.

Results: Genotype 5-HTTLPR-SL determined in 57.1% cases in severe obese children compared to simple one (34.0%), 5-HTTLPR-SS genotype 7.1% and 20.0%, respectively (χ²=6.0; P=0.05). There was no (χ²=5.0; P=0.7) significant differences between groups with obesity and control in the frequency of 5-HTTLPR-SS, 5-HTTLPR-SL, 5-HTTLPR-LL genotypes occurrence. We found more frequent depression occurrence in obese children and the presence of SS (40%) genotype compared to SL (4.5%) and LL (30%) (χ²=6.0 P=0.05). Serotonin levels were significantly higher in severe obese children and SS genotype 654.0 (425.0; 654.0) comparison to SL (315.6 (257.7; 403.7) ng/ml genotype (U=2.0, P=0.04). Significantly higher values of BMI were in group with severe obesity and SS genotype (44.7±2.0 kg/m²) than LL (38.5±3.0) (P=0.01) and SL (40.5±4.9) (P=0.04) genotypes. Children with simple obesity and SS-genotype (33.2±0.8) had higher BMI than with LL (31.7±3.2) (P=0.04) and SL (31.2±2.4) (P=0.003) genotypes.

Conclusion: Genotype 5-HTTLPR-SL were more often in severe obese children (57.1%) compared to simple one (34.0%) (P=0.05). Severe obese children with SS had higher BMI compared to LL (P=0.01) and SL (P=0.04) genotypes. Serotonin levels were higher in severe obese children with SS compared to SL genotype (P=0.04).