The Evolutionary Ecology of Mayor Histocampability Complex

School of Biological Sciences, University of Aberdeen, Zoology Building, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
Heredity (Impact Factor: 3.81). 02/2006; 96(1):7-21. DOI: 10.1038/sj.hdy.6800724
Source: PubMed


The major histocompatibility complex (MHC) has become a paradigm for how selection can act to maintain adaptively important genetic diversity in natural populations. Here, we review the contribution of studies on the MHC in non-model species to our understanding of how selection affects MHC diversity, emphasising how ecological and ethological processes influence the tempo and mode of evolution at the MHC, and conversely, how variability at the MHC affects individual fitness, population dynamics and viability. We focus on three main areas: the types of information that have been used to detect the action of selection on MHC genes; the relative contributions of parasite-mediated and sexual selection on the maintenance of MHC diversity; and possible future lines of research that may help resolve some of the unanswered issues associated with MHC evolution.

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    • "Selection on MHC genes is believed to be driven by pathogens and/or selective mate choice (Sommer 2005, Piertney and Oliver 2006). The spatial and temporal pattern of functional variation reflects the possibility for a population to adapt to novel conditions (Höglund 2009). "
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    • "Thus, the specific MHC class II allele setting of an individual determines directly its capability to resist or defend specific parasitic infections. The extraordinary high genetic diversity of the MHC genes is believed to be maintained by a number of non-neutral mechanisms (Bernatchez and Landry 2003; Piertney and Oliver 2006). Three major mechanisms have been hypothesized, based on heterozygote advantage, negative frequency-dependent selection, and fluctuating selection (Spurgin and Richardson 2010). "
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