Comparing more extreme degrees of obesity.

The data suggest an association when comparing more extreme degrees of obesity with normal controls, which is a potential explanation for the heterogeneity of the INSIG2 rs7566605 association with obesity (Hypothesis 2). Numbers stated are frequencies of risk genotype CC (C being the minor allele) across BMI categories for the Caucasian adult studies combined (All-CA) as well as stratified by study type (GP = general population, HP = healthy population, OB = obesity study). Also given are the p-values from testing for a trend of genotype frequencies across categories. (Not for All-NC or All-CH due to the few subjects in each category.)
aExcluding studies published before the response letter by Herbert et al., December 2006 [1] in which the hypothesis of potential heterogeneity due to study design and a first call for this meta-analysis were stated (i.e., excluding American_Polish, NHS, KORA_S4, Essen_trios, EPIC_Norfolk, MRC_Ely, DESIR, SHIP, OB_adult, which are all Caucasian studies).
bP-value testing for a trend across the BMI categories.

本数据显示，将重度肥胖人群与正常对照人群进行对比时存在关联，这为胰岛素诱导基因2（INSIG2）rs7566605位点与肥胖关联的异质性提供了一种潜在解释（假说2）。此处列出的数值为合并所有高加索成人研究（All-CA）后，不同身体质量指数（Body Mass Index，BMI）类别下风险基因型CC（C为次要等位基因）的频率，同时也按研究类型进行了分层：GP=普通人群（general population）、HP=健康人群（healthy population）、OB=肥胖研究（obesity study）。同时还给出了不同BMI类别间基因型频率趋势检验的p值（由于All-NC与All-CH组的每类样本量均极少，故未提供该组数据）。
a 排除了2006年12月Herbert等人发表的回应函[1]之前的相关研究：该回应函首次提出了研究设计导致异质性的假说，并首次发起本项荟萃分析。需排除的高加索人群研究包括：American_Polish、NHS、KORA_S4、Essen_trios、EPIC_Norfolk、MRC_Ely、DESIR、SHIP、OB_adult。
b 不同BMI类别间基因型频率趋势检验的p值。