配对病例对照研究基因与基因交互作用样本量的确定

目的 采用配对病例对照研究探讨基因与基因交互作用所需的样本量。方法 logistic回归分析原理建立两基因与一种疾病相关性模型,以模拟参数值回代计算样本量,计算过程以QUANTO软件完成。结果(1)基因交互作用越大,所需样本量越少;基因型分布频率P_r为35％(相当于显性遗传模型易感基因频率等于0.20、阴性遗传模型易感基因频率等于0.60)时,基因交互作用的样本量最少:如两基因主作用均为2,基因交互作用为2时样本量为700例;基因交互作用为5时样本量为200例。(2)探讨基因主作用与探讨基因交互作用所需的样本量不同。结论 提供了可供查阅的两基因交互作用样本含量值。

Sam ple size requirements for association studies on gene-gene interaction in case-control study

Objective Sample size requirements for association studies on gene-gene interaction incase-control study. Methods Selecting different parameters (such as inheritance mode, susceptibilityfrequency, frequency of allele for disease, OR of gene main effect) and infilling them into QUANTOsoftware based on conditional logistic regression mode. Results (1)The main parameters influencing thesample size requirements were the levels of interaction between genes and the susceptibility frequency. Thenumbers of sample were the same between recessive and dominant when susceptibility frequeney were thesame. (2) Sample size for testing of gene-gene interaction was different from that for testing of geneticeffects. Conclusion It was convenient to use the numbers of sample size from the results for gene-geneinteraction in case-control study.