Chiano M N, Yates J R
Statistical Laboratory, University of Cambridge, UK.
Ann Hum Genet. 1995 Jan;59(1):83-95. doi: 10.1111/j.1469-1809.1995.tb01607.x.
Linkage analysis has contributed to the localization of many human disease genes. The presence of locus heterogeneity reduces statistical power and can prejudice the detection of linkage if the analysis assumes homogeneity. Nevertheless, mixed genetic models are not routinely used in gene searches. The null distribution of the test statistic is not uniquely defined. In this paper, a transformation is used to determine an approximate asymptotic distribution of the test statistic under a mixture model. The equivalent critical values of the test are computed and the performance of the test under various levels of heterogeneity and family size is investigated. For gene searches, we recommend the routine use of an admixture model with a critical lod score of 3.44.
连锁分析有助于许多人类疾病基因的定位。如果分析假设基因座是同质的，那么基因座异质性的存在会降低统计功效，并可能影响连锁的检测。然而，混合遗传模型在基因搜索中并未被常规使用。检验统计量的零分布没有唯一确定。在本文中，我们使用一种变换来确定混合模型下检验统计量的近似渐近分布。计算了检验的等效临界值，并研究了在不同异质性水平和家系大小下检验的性能。对于基因搜索，我们建议常规使用临界对数优势分数为3.44的混合模型。
