Investigation of mechanisms underlying obesity amongst Chinese, Malays and Indians in Singapore

Abstract

In Singapore, Malays and Indians exhibit higher obesity susceptibility compared to the Chinese. I investigated whether genetic, dietary, physical activity, sleep and gut microbial factors could explain this disparity. Whole genome sequencing data and lifestyle traits quantified using validated questionnaires of ~10,000 individuals were utilized. Gut microbial factors based on shotgun metagenomic data were studied for their relationship with adiposity and adiposity loss post lifestyle-intervention. There were no significant differences in risk allele frequencies and effect sizes of BMI-related variants. Polygenic risk score, saturated fat and fiber consumption, engagement in vigorous physical activities, duration and quality of sleep, snoring, Eggerthella lenta, Klebsiella grimontii, as well as three microbial pathways (involving fatty acid and membrane component synthesis) were all significantly associated with adiposity. However, these factors did not fully explain the higher obesity rates in Malays and Indians. More research is needed to explore other mechanisms underlying adiposity within Asian populations. (150 words)