No evidence for MHC class I based disassortative mating in a wild population of great tits

Genes of the major histocompatibility complex (MHC) are regarded as a potentially important target of mate choice due to the fitness benefits that may be conferred to the offspring. According to the complementary genes hypothesis, females mate with MHC dissimilar males to enhance the immunocompetence of their offspring or to avoid inbreeding depression. Here, we investigate whether selection favours a preference for maximally dissimilar or optimally dissimilar MHC class I types, based on MHC genotypes, average amino acid distances and the functional properties of the antigen-binding sites (MHC supertypes); and whether MHC type dissimilarity predicts relatedness between mates in a wild great tit population. In particular, we explore the role that MHC class I plays in female mate choice decisions while controlling for relatedness and spatial population structure, and examine the reproductive fitness consequences of MHC compatibility between mates. We find no evidence for the hypotheses th...主要组织相容性复合体（major histocompatibility complex，MHC）基因因可赋予后代适合度收益，被视作配偶选择的潜在重要靶标。依据互补基因假说，雌性个体通过与MHC相异的雄性交配，以提升后代的免疫能力或规避近交衰退。本研究基于MHC基因型、平均氨基酸距离以及抗原结合位点的功能特性（MHC超型），探究选择是否青睐最大化相异或最适相异的MHC I类基因类型；同时在野生大山雀种群中，验证MHC类型相异性是否可预测配偶间的亲缘关系。尤为关键的是，本研究在控制亲缘关系与空间种群结构的前提下，探讨MHC I类基因在雌性配偶选择决策中的作用，并检验配偶间MHC相容性对繁殖适合度的相关后果。本研究未发现支持上述假说的证据……