Simple multiple-marker sib-pair analysis for mapping quantitative trait loci.

摘要

A simple and robust method for detecting quantitative trait loci (QTL) by their linkage to a single marker using information from sib-pairs has been described previously [Behavioural Genetics (1972) 2, 3-19]. The method involves the regression of the squared difference between the phenotypic scores onto the proportion of alleles at the marker which are identical by descent. The availability of genetic maps of marker loci makes it possible to extend this method to incorporate information from several marker loci. It was shown that by considering identity by descent from the 2 parents separately, a method can be devised to use information from multiple markers to estimate the proportion of alleles identical by descent for a QTL in any given location. The method can also be extended to allow for differences in recombination frequencies between the sexes and more complicated relationships between individuals. It was shown by simulation that this method is as powerful as the alternative least squaresapproaches using multiple markers and provides more accurate estimates.