Patterns of diversity and spatial variability of β-defensin innate immune genes in a declining wild population of tree swallows

Assessing the genetic variation and distribution of immune genes across heterogeneous environmental conditions in wild species is essential to further our understanding of the role of pathogen pressure and potential resistance or prevalence in hosts. Researchers have recently investigated β-defensin genes in the wild, because their variability suggests that they may play an important role in innate host defense. This study investigated the variation occurring at 6 innate immune genes of the β-defensin family in a declining population of tree swallows (Tachycineta bicolor) in southern Québec, Canada (N = 160). We found that all 6 genes showed synonymous and nonsynonymous single nucleotide polymorphisms (SNPs) within the exon coding for the mature peptide. These results indicated that this group of genes was diverse in tree swallows. Our results suggested a potential interaction of this group of genes with fluctuating pathogen diversity, however, we found no sign of positive or negative s...

评估野生物种中免疫基因的遗传变异及其在异质环境中的分布特征，对于深入解析病原体压力的作用机制，以及宿主的潜在抗性或感染流行情况至关重要。近期研究者针对野生环境中的β防御素（β-defensin）基因展开了调查，因其变异特征提示其可能在宿主先天免疫防御中发挥关键作用。本研究针对加拿大魁北克南部一处正在衰退的树燕（Tachycineta bicolor）种群（样本量N=160）中β防御素家族的6种先天免疫基因的变异情况进行了探究。我们发现，这6种基因在编码成熟肽的外显子区域均存在同义与非同义单核苷酸多态性（single nucleotide polymorphisms, SNPs）。上述结果表明，树燕体内的该类基因具有丰富的遗传多样性。研究结果提示该类基因或许与波动的病原体多样性存在潜在相互作用，但我们未发现阳性选择或阴性选择的相关迹象……