Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore; and Khoo Teck Puat - National University Children's Medical Institute, National University Health System, NUHS Tower Block, Level 12, 1E Kent Ridge Road, Singapore, 119228, Singapore.
Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore.
Nutr J. 2018 Feb 24;17(1):31. doi: 10.1186/s12937-018-0340-3.
Recent genome-wide association studies (GWAS) have identified 97 body-mass index (BMI) associated loci. We aimed to evaluate if dietary intake modifies BMI associations at these loci in the Singapore Chinese population.
We utilized GWAS information from six data subsets from two adult Chinese population (N = 7817). Seventy-eight genotyped or imputed index BMI single nucleotide polymorphisms (SNPs) that passed quality control procedures were available in all datasets. Alternative Healthy Eating Index (AHEI)-2010 score and ten nutrient variables were evaluated. Linear regression analyses between z score transformed BMI (Z-BMI) and dietary factors were performed. Interaction analyses were performed by introducing the interaction term (diet x SNP) in the same regression model. Analysis was carried out in each cohort individually and subsequently meta-analyzed using the inverse-variance weighted method. Analyses were also evaluated with a weighted gene-risk score (wGRS) contructed by BMI index SNPs from recent large-scale GWAS studies.
Nominal associations between Z-BMI and AHEI-2010 and some dietary factors were identified (P = 0.047-0.010). The BMI wGRS was robustly associated with Z-BMI (P = 1.55 × 10) but not with any dietary variables. Dietary variables did not significantly interact with the wGRS to modify BMI associations. When interaction analyses were repeated using individual SNPs, a significant association between cholesterol intake and rs4740619 (CCDC171) was identified (β = 0.077, adjP = 0.043).
The CCDC171 gene locus may interact with cholesterol intake to increase BMI in the Singaporean Chinese population, however most known obesity risk loci were not associated with dietary intake and did not interact with diet to modify BMI levels.
最近的全基因组关联研究（GWAS）已经确定了 97 个与体重指数（BMI）相关的基因座。我们旨在评估在新加坡华人人群中，这些基因座的饮食摄入是否会改变 BMI 关联。
我们利用了来自两个成人华人群体的六个数据子集的 GWAS 信息（N=7817）。所有数据集都有 78 个经过质量控制程序的基因分型或推断的指数 BMI 单核苷酸多态性（SNP）。评估了替代健康饮食指数（AHEI）-2010 评分和十个营养素变量。在相同的回归模型中，通过引入交互项（饮食 x SNP）来进行线性回归分析。在每个队列中单独进行分析，然后使用逆方差加权法进行荟萃分析。分析还使用了来自最近大规模 GWAS 研究的 BMI 指数 SNP 构建的加权基因风险评分（wGRS）进行了评估。
Z-BMI 与 AHEI-2010 和一些饮食因素之间存在显著关联（P=0.047-0.010）。BMI wGRS 与 Z-BMI 显著相关（P=1.55×10），但与任何饮食变量无关。饮食变量与 wGRS 没有显著相互作用来改变 BMI 关联。当使用个体 SNP 重复进行交互分析时，发现胆固醇摄入量与 rs4740619（CCDC171）之间存在显著关联（β=0.077，adjP=0.043）。
CCDC171 基因座可能与胆固醇摄入相互作用，增加新加坡华人的 BMI，但大多数已知的肥胖风险基因座与饮食摄入无关，也不会与饮食相互作用来改变 BMI 水平。
