Charbonnel Nathalie, Bryja Josef, Galan Maxime, Deter Julie, Tollenaere Charlotte, Chaval Yannick, Morand Serge, Cosson Jean-François
Centre de Biologie et Gestion des Populations UMR (INRA/IRD/Cirad/Montpellier SupAgro), INRA-EFPA Montferrier sur Lez Cedex, France.
Centre de Biologie et Gestion des Populations UMR (INRA/IRD/Cirad/Montpellier SupAgro), INRA-EFPA Montferrier sur Lez Cedex, France ; Department of Population Biology, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic Studenec, Czech Republic.
Evol Appl. 2010 May;3(3):279-90. doi: 10.1111/j.1752-4571.2009.00108.x. Epub 2010 Jan 25.
Heterogeneities in immune responsiveness may affect key epidemiological parameters and the dynamics of pathogens. The roles of immunogenetics in these variations remain poorly explored. We analysed the influence of Major histocompatibility complex (Mhc) genes and epigamic traits on the response to phytohaemagglutinin in males from cyclic populations of the montane water vole (Arvicola scherman). Besides, we tested the relevance of lateral scent glands as honest signals of male quality. Our results did not corroborate neither the hypotheses of genome-wide heterozygosity-fitness correlation nor the Mhc heterozygote advantage. We found a negative relationship between Mhc hetetozygosity and response to phytohaemagglutinin, mediated by a specific Mhc homozygous genotype. Our results therefore support the hypothesis of the Arte-Dqa-05 homozygous genotype being a 'good' Mhc variant in terms of immunogenetic quality. The development of the scent glands seems to be an honest signal for mate choice as it is negatively correlated with helminth load. The 'good gene' hypothesis was not validated as Arte-Dqa-05 homozygous males did not exhibit larger glands. Besides, the negative relationship observed between the size of these glands and the response to phytohaemagglutinin, mainly for Mhc homozygotes, corroborates the immunocompetence handicap hypothesis. The Mhc variants associated with larger glands remain yet to be determined.
免疫反应的异质性可能会影响关键的流行病学参数和病原体的动态变化。免疫遗传学在这些变异中的作用仍未得到充分探索。我们分析了主要组织相容性复合体（Mhc）基因和求偶性状对来自山地水田鼠（Arvicola scherman）周期性种群雄性个体对植物血凝素反应的影响。此外，我们测试了侧嗅腺作为雄性质量诚实信号的相关性。我们的结果既没有证实全基因组杂合度与适应性相关性的假设，也没有证实Mhc杂合子优势的假设。我们发现Mhc杂合性与对植物血凝素的反应之间存在负相关，这是由一种特定的Mhc纯合基因型介导的。因此，我们的结果支持了Arte - Dqa - 05纯合基因型在免疫遗传质量方面是一种“良好”Mhc变体的假设。嗅腺的发育似乎是一个用于配偶选择的诚实信号，因为它与蠕虫负荷呈负相关。“好基因”假设未得到验证，因为Arte - Dqa - 05纯合雄性个体并未表现出更大的腺体。此外，主要针对Mhc纯合子观察到的这些腺体大小与对植物血凝素反应之间的负相关，证实了免疫能力缺陷假设。与较大腺体相关的Mhc变体仍有待确定。
