ESPE Abstracts

Study aim was to evaluate the contribution of DRD2 gene TaqIA polymorphism, plasma leptin and dopamine concentrations to obesity development in children with different adiposity classes, depending on gender and pubertal stage.

Materials and methods: 223 children aged from 11 to 17.9 years were involved in the retrospective one-stage analysis, 179 of them were randomly genotyped in the TaqIA of DRD2 gene and blood dopamine (BD) concentrations were detected. Children were split up in terms of BMI SDS into three groups: the first – normal weight (NW) (±1, n=30), the second — alimentary obesity (AO) (BMI≥+2, <+4, n=86), the third — extreme obesity (EO) (≥+4, n=107). These groups were split off by gender (f/m, n=112/111) and pubertal periods (preprubertal–the 1st Tanner stage; early pubertal–the 2nd +3rd Tanner stage; late pubertal–the 4th+5th Tanner stage) Statistical analysis were performed by means of SPSS 21.0 (P < 0.05) with data shown as a median and quartile range (25–75).

Results: Children with EO had increased D levels 31.88 (7.82–99.38) in comparison with NW kids–6.28 (4.57–26.54) (P=0.002), and AO patients with 10.44 (4.80–46.88) pg/ml BD (P=0.008). The same pattern had EO boys with BD 31.88 (9.69–93.75) compared to NW kids–6.46 (3.73–26.54) (P=0.002), and AO patients with 7.83 (4.47–13.04) pg/ml BD (P=0.008). Early pubertal male: AO patients had the lowest plasma D 4.84 (3.54–9.32), that were significantly differ than NW children (8.20 (5.96–56.25) pg/ml; P=0.046) and EO ones (5.78 (4.62–19.38) pg/ml; P=0.002). NW late pubertal boys had minimal D levels (5.96 (3.73–14.16)) pg/ml with gradual D raising in AO (14.53 (6.55–65.63) pg/ml; P=0.01) and EO groups (48.75 (11.68–114.25) pg/ml; P=0.0001). Children with AO and EO had raised A1 TaqI DRD2 allele frequencies: in 50% and 40% equally in contrast with NW patients (10%) (P=0.015). AO boys had more frequent TaqI A1 polymorphism of DRD2-gene (66.7%) compared to EO (23.8%) and NW boys (14.3%), P=0.05.

Conclusions: Patients with AO and EO had enlarged prevalence of the high L and D concentrations in comparison with NW children, who had decreased and low these neuropeptides levels. TaqI A1 polymorphism of DRD2-gene was more prevalent in AO and EO patients as opposed to NW children (P=0.015).