We present a general regression-based method for mapping quantitative trait
loci (QTL) by combining different populations derived from diallel designs
. The model expresses, at any map position, the phenotypic value of each in
dividual as a function of the specific-mean of the population to which the
individual belongs, the additive and dominance effects of the alleles carri
ed by the parents of that population and the probabilities of QTL genotypes
conditional on those of neighbouring markers. Standard linear model proced
ures (ordinary or iteratively reweighted least-squares) are used for estima
tion and test of the parameters.