Taq1a polymorphism (rs1800497) is associated with obesity-related outcomes and dietary intake in a multi-ethnic sample of children.

Abstract

In adults, the Taq1a polymorphism (rs1800497) near the D2 receptor (DRD2) gene is associated with body mass index and binge eating and is more prevalent among non-Hispanic Blacks (NHB) and Hispanic-Americans (HA) relative to non-Hispanic Whites (NHW). We hypothesize Taq1a polymorphism (rs1800497) risk alleles contribute to paediatric racial/ethnic differences in obesity phenotypes. This study aims to characterize the relationship between the Taq1a polymorphism (rs1800497), diet and adiposity in a multi-ethnic cohort of 286 children (98 NHB, 76 HA and 112 NHW), ages 7-12. Dual-energy X-ray absorptiometry, computed tomography scans and two 24-h dietary recalls assessed body composition, fat distribution and dietary intakes, respectively. Children with two Taq1a risk alleles (NHB=50.0%, HA=43.3%, NHW=6.7%) reported a 20% increase in total energy intake (P=0.0034) and per cent of calories from sugar consumed (P=0.0077) than did children with less than two risk alleles. Children with two Taq1a risk alleles demonstrated significantly higher total body fat (P=0.0145), body fat percentage (P=0.0377), intra-abdominal adiposity (P=0.0459), subcutaneous abdominal adiposity (P=0.0213) and total abdominal adiposity (P=0.0209) than did children with one or no Taq1a risk alleles. Our results suggest that having two Taq1a risk alleles is associated with an increase in reported calorie and sugar consumption and is a potential risk factor for early development of excess adiposity in multi-ethnic children. These results need to be confirmed in a larger sample.