[Association between rs10938397 polymorphism in GNPDA2 and obesity in children at different stages of development]

Objective: To examine the association between rs10938397 polymorphism in glucosamine-6-phosphate deaminase 2 (GNPDA2) and risk of obesity in children at different stages of development and analyze the differences in the association. Methods: A total of 3 503 school-aged children were selected from the Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study in Beijing and their complete anthropometry weight, height, fat mass percentage (FMP), fat mass index (FMI) and free fat mass index (FFMI) and sexual maturation (SM) data were used. The developmental stages were evaluated using male testicular volume and female breast Tanner staging. FMP, FM and FFM were measured by bioelectrical impedance analysis. General obesity and adiposity were respectively defined according to Chinese sex-age-specific body mass index (BMI) cutoffs and sex-age-specific FMP cutoffs. The SNP rs10938397 were genotyped by the TaqMan Allelic Discrimination Assay with the GeneAmp 7900 sequence detection system (Applied Biosystems, Foster city, CA, USA). Relationships between rs10938397 polymorphism and BMI, FMP, FMI and FFMI and different types of obesity were tested using multivariate linear regression and logistic regression models. Results: After age adjustment and correction for multiple testing, the rs10938397-G was associated with BMI and risk of general obesity in boys in early puberty (β=0.328, P=0.001; OR=1.420, 95%CI: 1.126-1.790), and the rs10938397-G was associated with BMI in girls in late puberty (β=0.266, P=0.001). The associations of GNPDA2 rs10938397-G with FFMI and FMI were observed in boys in early puberty (β=0.137, P=0.016; β=0.202, P=0.007) and the associations of rs10938397-G with FMP and FMI were observed in girls in late puberty (β=0.153, P=0.002; β=0.168, P=0.001). The rs10938397-G was also associated with adiposity in girls in late puberty (OR=1.339, 95%CI: 1.093-1.637). Conclusion: The rs10938397 polymorphism in GNPDA2 is associated with adiposity in girls, and it is important to use an accurate indicator of obesity in exposing the genuine association between genes and obesity.