MINIMUM SAMPLE-SIZE ESTIMATION TO DETECT GENE ENVIRONMENT INTERACTION IN CASE-CONTROL DESIGNS
MINIMUM SAMPLE-SIZE ESTIMATION TO DETECT GENE ENVIRONMENT INTERACTION IN CASE-CONTROL DESIGNS
复制标题
DOI：
10.1093/oxfordjournals.aje.a117193
复制
发表时间：
1994-12-01
影响因子：
5
通讯作者：
KHOURY, MJ
中科院分区：
文献类型：
--
作者：
HWANG, SJ;BEATY, TH;KHOURY, MJ
随着遗传标记越来越容易获得，病例对照研究在确定遗传因素在疾病因果关系中的作用方面将越来越重要。作者估计了最小样本量，以确保足够的统计能力来检测基因-环境相互作用。一个假设是：在对照中，暴露的流行与标记基因型无关。根据这一假设，6个参数（3个优势比、暴露的流行程度、易感基因型的比例以及对照与病例的比例）决定了2 x 2 x 2表中对比遗传易感性、暴露和疾病的预期细胞大小。这三个比值比反映了非易感人群中疾病与暴露之间的关系；2)未暴露个体的易感基因型；3)基因-环境相互作用本身。根据这些参数，可以估计出确保任何特定的第一类和第二类错误率所需的病例和控制的数量。本文的结果表明，病例对照设计可用于检测基因-环境相互作用，当存在共同暴露和高度多态性的易感性标记时。
As genetic markers become more available, case-control studies will be increasingly important in defining the role of genetic factors in disease causality. The authors estimate the minimum sample size needed to assure adequate statistical power to detect gene-environment interaction. One assumption is made: the prevalence of exposure is independent of marker genotypes among controls. Given the assumption, six parameters (three odds ratios, the prevalence of exposure, the proportion of those with the susceptible genotype, and the ratio of controls to cases) dictate the expected cell sizes in a 2 x 2 x 2 table contrasting genetic susceptibility, exposure, and disease. The three odds ratios reflect the association between disease and I) exposure among non-susceptibles; 2) susceptible genotypes among nonexposed individuals; and 3) the gene-environment interaction itself, respectively. Given these parameters, the number of cases and controls needed to assure any particular Type I and Type II error rates can be estimated. Results presented here demonstrate that case-control designs can be used to detect gene-environment interaction when there is both a common exposure and a highly polymorphic marker of susceptibility.