MAXIMUM-LIKELIHOOD MODELS FOR MAPPING GENETIC-MARKERS SHOWING SEGREGATION DISTORTION .1. BACKCROSS POPULATIONS

A maximum-likelihood approach is used in order to estimate recombinati on fractions between markers showing segregation distortion in backcro ss populations. It is assumed that the distortions are induced by viab ility differences between gametes or zygotes due to one or more select ed genes. We show that Bailey's (1949) estimate stays consistent and e fficient under more general assumptions than those defined by its auth or. This estimate should therefore be used instead of the classical ma ximum-likelihood estimate. The question of detection of linkage is als o discussed. We show that the order of markers on linkage groups may b e affected by segregation distortion.