Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
Medical Research Unit in Biochemistry, Hospital de Especialidades, Centro Médico Nacional Siglo XXI del Instituto Mexicano del Seguro Social, Mexico City, Mexico.
Obesity (Silver Spring). 2016 Sep;24(9):1989-95. doi: 10.1002/oby.21590. Epub 2016 Aug 3.
The prevalence of obesity in Mexico has increased at an alarming rate in both adults and children. This study was undertaken to test in Mexican children the effects of single nucleotide polymorphisms (SNP) that have been associated with body mass index (BMI) and obesity in Europeans.
School-age children (N = 1,559, 5-17 years) were recruited in Mexico City. Thirty-five SNPs with established effects on BMI and obesity were genotyped and analyzed individually and as a combined gene score (GS).
SNPs in FAIM2 (rs7138803), GPRC5BB (rs12444979), MTIF3 (rs4771122), TFAP2B (rs987237), TMEM18 (rs7561317), and the GS were significantly associated with BMI. The GS explained 0.9% of the variance of BMI. Also, SNPs in LRRN6C (rs10968576) and MC4R (rs17782313) were significantly associated with overweight and obesity categories, respectively. Importantly, the effect allele frequency of 26/35 SNPs (74.3%) differed significantly between Mexican children and European adults. No significant gene × environment or gene × gene interactions were detected after Bonferroni adjustment.
Several SNPs first associated with BMI/obesity in European adults replicated well in Mexican children, and investigating differences in the distribution of effect alleles across ethnic populations may shed light on genetic susceptibilities of different populations to obesity.
墨西哥成年人和儿童的肥胖患病率均以惊人的速度上升。本研究旨在检测与欧洲人体重指数（BMI）和肥胖相关的单核苷酸多态性（SNP）在墨西哥儿童中的作用。
在墨西哥城招募了学龄儿童（N=1559 人，年龄 5-17 岁）。对 35 个与 BMI 和肥胖相关的 SNP 进行基因分型，并单独和作为综合基因评分（GS）进行分析。
FAIM2（rs7138803）、GPRC5BB（rs12444979）、MTIF3（rs4771122）、TFAP2B（rs987237）、TMEM18（rs7561317）和 GS 的 SNP 与 BMI 显著相关。GS 解释了 BMI 方差的 0.9%。此外，LRRN6C（rs10968576）和 MC4R（rs17782313）的 SNP 分别与超重和肥胖类别显著相关。重要的是，35 个 SNP 中的 26/35 个（74.3%）的效应等位基因频率在墨西哥儿童和欧洲成年人之间存在显著差异。经 Bonferroni 调整后，未检测到基因×环境或基因×基因相互作用。
首次在欧洲成年人中与 BMI/肥胖相关的多个 SNP 在墨西哥儿童中得到了很好的复制，研究不同种族群体中效应等位基因分布的差异可能有助于揭示不同人群对肥胖的遗传易感性。
