NEW PERSPECTIVES ON MATE CHOICE AND THE MHC

A long series of studies on mice has shown that mate choice decisions can be made on the basis of individual genotype at the major histocomp atibility complex (MHC), which accords well with the importance of imm unocompetence in some theories of sexual selection. Recent work on oth er vertebrate species, including humans, indicates that MHC-based mate choice is not restricted to the genus Mus. However, its importance ma y vary among species as a result of differences in social and mating s ystem structure, and perhaps genome structure. There appears to be a g eneral preference expressed for MHC-dissimilar mates, and such MHC-dis assortative mating may be involved in maintaining MHC and/or genome-wi de diversity in natural populations. The strength and direction of MHC -based mating preference can vary, and may be modulated by factors suc h as genetic background, sex, and early life experience.