Pc. Sham et al., Variance-components QTL linkage analysis of selected and non-normal samples: Conditioning on trait values, GENET EPID, 19, 2000, pp. S22-S28
Standard variance-components quantitative trait loci (QTL) linkage analysis
can produce an elevated rate of type 1 errors when applied to selected sam
ples and non-normal data. Here we describe an adjustment of the log-likelih
ood function based on conditioning on trait values. This leads to a likelih
ood ratio test that is valid in selected samples and non-normal data, and e
qual in power to alternative methods for analyzing selected samples that re
quire knowledge of the ascertainment procedure or the trait values of non-s
elected individuals. Genet. Epidemiol. 19(Suppl 1):S22-S28, 2000. (C) 2000
Wiley-Liss, Inc.