Association of Brain-Derived Neurotrophic Factor (BDNF) Variant (rs6265) with Overweight/Obesity orOverfatness, and Effect of Physical Activity Levels in Adolescents Population

Childhood and adolescents obesity are worldwide health issue, characterized by various somatic, psychosocial and psychiatric complications, which translates to adult obesity and other related complications. Brain-derived neurotrophic factor (BDNF) is a neurotrophin that mediates feeding habit, food intake, energy metabolism and weight control. A common variant of the BDNF gene (rs6265) has been associated with various forms of eating disorders, influencing body mass index (BMI) and obesity in various populations. Yet, no similar finding was reported on Malaysian adolescents population to date. The aim of this study was to determine the association between this variant and obesity, and to ascertain the influence of physical activity levels on the variant in 564 Malaysian adolescents of different ethnic background. We genotyped the variant using TaqMan-based allele-specific PCR assay and the result was analysed using SPSS statistical analysis software, in line with levels of physical activity recorded earlier on. Comparison between overweight/obese and lean individuals revealed that rs6265 A risk allele which is also theminor allele was significantly associated with risk for overweight/obese (pless than0.001; OR=3.0; 95 %-CI=1.49-4.15) and overfatness (p=0.012; OR=1.06; 95 %-CI=0.52-1.68) in the study population. We also observed a significant association (p=0.046) between the minor allele and physical activity. This finding is the first of its kind to reveal significant association between the variant mentioned above, physical activities and obesity in multi-ethnic Malaysian adolescents population which confirmed several findings in other populations.