NEW PERSPECTIVES ON MATE CHOICE AND THE MHC

A long series of studies on mice have shown that mate choice decisions can be made on the basis of individual genotype at the major histocam patibility complex (MHC), which accords well with the importance of im munocompetence in some theories of sexual selection. Recent work on ot her vertebrate species, including humans, indicates that MHC-based mat e choice is not restricted to the genus Mus. However, its importance m ay vary among species as a result of differences in social and mating system structure, and perhaps genome structure. There appears to be a general preference expressed for MHC-dissimilar mates, and such MHC-di sassortative mating may be involved in maintaining MHC and/or genome-w ide diversity in natural populations. The strength and direction of MH C-based mating preference can vary, and may be modulated by factors su ch as genetic background, sex, and early life experience.