Allele frequencies in multigene families II. Coalescent approach

Shimizu's model for the evolution of multigene families, subject to gene conversion and mutation, is studied. The probability distribution for the allelic configuration of two chromosomes is found, by using “coalescent” methods. For the two chromosomes, moments are found for the number of alleles they have in common and for their total number of alleles, together with the probability that there is only one allele present. Some numerical examples are given.