全基因组关联分析(genome-wide association study,GWAS)是近年来兴起的遗传分析方法,在人类和动植物复杂性状遗传研究中已取得初步成果。本文论述了GWAS研究的基本原理、主要分析方法及常用软件,在人类和动植物复杂性状研究中的应用;分析了GWAS研究中"丢失遗传率"的主要影响因素;介绍了上位性分析的新策略和基于GPU并行计算和混合线性模型的分析软件QTXNetwork;展望了GWAS研究的发展方向。
QTLs for heading date of rice （Oryza sativa L.） with additive, epistatic, and QTL × environment （QE） interaction effects were studied using a mixed-model-based composite interval mapping （MCIM） method and a double haploid （DH） population derived from IR64/Azucena in two crop seasons. Fourteen QTLs conferring heading date in rice, which were distributed on ten chromosomes except for chromosomes 5 and 9, were detected. Among these QTLs, eight had single-locus effects, five pairs had double-locus interaction effects, and two single-loci and one pair of double-loci showed QTL × environment interaction effects. All predicted values of QTL effects varied from 1.179 days to 2.549 days, with corresponding contribution ratios of 1.04%-4.84%. On the basis of the effects of the QTLs, the total genetic effects on rice heading date for the two parents and the two superior lines were predicted, and the putative reasons for discrepancies between predicted values and observed values, and the genetic potentiality in the DH population for improvement of heading date were discussed. These results are in agreement with previous results for heading date in rice, and the results provide further information, which indicate that both epistasis and QE interaction are important genetic basis for determining heading date in rice.
