Peroxisome proliferator-activated receptor-γ (PPARγ) Pro12Ala polymorphism and risk for pediatric obesity

Background: Variation in the peroxisome-proliferator-activated receptor γ (PPARγ) gene has been reported to alter the risk for adiposity in adults. Methods: We investigated the gender related association between the Pro12Ala variant (rs1801282) in obesity and insulin resistance traits in 794 peri-adolescent children aged 10–12 years of Greek origin from the Gene and Diet Attica Investigation (GENDAI) cohort. Results: Gender stratified analysis suggested that in peri-adolescent boys, Ala carriers exhibited lower measures of skinfold (triceps: 16.9±6.9 vs. 19.4±7.9 mm, p=0.014; subscapular: 9.6±4.5 vs. 11.2±5.4 mm, p=0.016) and lower adiponectin concentrations (3.9±1.3 vs. 4.7±2.4 μg/mL, p=0.05). In peri-adolescent girls, Ala carriers had lower insulin concentrations (7.3±3.7 vs. 8.5±4.4 μU/mL, p=0.026) and lower values of homeostasis model assessment of insulin resistance (HOMA-IR) (1.5±0.8 vs. 1.8±0.96, p=0.019). Linear regression analysis revealed that the presence of the Ala allele in boys was a nominally significant predictor of obesity indices, including skin-folds (triceps: β±SE: –2.3±1.1, p=0.032; subscapular: β±SE: –2.3±1.1, p=0.04) and adiponectin concentrations (β±SE: –0.7±0.4, p=0.05) after adjusting for potential covariates. In girls, the Ala allele was a predictor of insulin concentrations (β±SE: –1.2±0.6, p=0.037) and HOMA-IR (β±SE: –0.24±0.13, p=0.037).Conclusions: Our results suggest that adiposity in children is influenced by the Pro12Ala polymorphism in a gender specific manner. Clin Chem Lab Med 2009;47:1047–50.Peer Reviewe

The Gene-Diet Attica investigation on childhood obesity (GENDAI):overview of the study design

BACKGROUND: There is limited evidence on the role of genetic and environmental factors in the etiology of childhood obesity, a major health problem worldwide. METHODS: The Gene-Diet Attica Investigation on childhood obesity (GENDAI) evaluates the contributions to and pivotal interactions of genetic, dietary and physical activity variables on children's weight. We describe the design, methodology, and present preliminary data. So far, 920 participants have been enrolled and the final projected sample is 1000 fifth- and sixth-grade students from selected elementary schools in Attica (10-14 years). In this school-based cross-sectional study, more than 400 variables describing anthropometric, dietary, clinical, genetic, sociodemographic and other lifestyle characteristics were collected from participating children and their families. RESULTS: Increased body mass index was identified in 39.3% of subjects (30.5% overweight and 8.8% obese), with males presenting a more unfavorable metabolic profile, i.e., higher blood lipids, glucose, and insulin, compared to females. Normal-weight children had a significant advantage when compared to all children of increased weight in terms of lipid profile and insulin, as well as behaviors examined. Specifically, normal-weight children exhibited less skipping of meals and less sedentary activities. CONCLUSIONS: The overall high prevalence of overweight and obesity in the current population is significant and underscores the need for environmental and genetic information that will shed light on the phenomenon of childhood obesity