Data from: Blood transcriptomes and de novo identification of candidate loci for mating success in lekking great snipe (Gallinago media)

We assembled the great snipe blood transcriptome using data from fourteen lekking males, in order to de novo identify candidate genes related to sexual selection, and determined the expression profiles in relation to mating success. The three most highly transcribed genes were encoding different haemoglobin subunits. All tended to be overexpressed in males with high mating success. We also called Single Nucleotide Polymorphisms (SNPs) from the transcriptome data and found considerable genetic variation for many genes expressed during lekking. Among these we identified 14 polymorphic candidate SNPs that had a significant genotypic association with mating success (number of females mated with) and/or mating status (mated or not). Four of the candidate SNPs were found in HBAA (encoding the haemoglobin α-chain). Heterozygotes for one of these and one SNP in the gene PABPC1 appeared to enjoy higher mating success compared to males homozygous for either of the alleles. In a larger dataset of individuals we genotyped 38 of the identified SNPs but found low support for consistent selection since only one of the zygosities of previously identified candidate SNPs and none of their genotypes were associated with mating status. However, candidate SNPs generally showed lower levels of spatial genetic structure compared to non-candidate markers. We also scored the prevalence of avian malaria in a sub-sample of birds. Males infected with avian malaria parasites had lower mating success in the year of sampling than non-infected males. Parasite infection and its interaction with specific genes may thus affect performance on the lek.本研究利用14只求偶场雄性大沙锥的测序数据组装了大沙锥的血液转录组，旨在从头识别与性选择相关的候选基因，并解析与交配成功率相关的基因表达谱。转录水平最高的三个基因均编码不同的血红蛋白亚基，且在交配成功率较高的雄性个体中均呈现过表达趋势。我们还从转录组数据中检测了单核苷酸多态性（Single Nucleotide Polymorphisms, SNPs），并发现求偶期表达的诸多基因存在显著的遗传变异。在此之中，我们鉴定出14个多态性候选SNP，其基因型与交配成功率（即交配雌性数量）和/或交配状态（是否完成交配）存在显著关联。其中4个候选SNP位于HBAA基因（编码血红蛋白α链）中。与携带任一等位基因纯合子的雄性个体相比，上述其中一个SNP与PABPC1基因中某一SNP的杂合子个体展现出更高的交配成功率。在更大规模的个体数据集内，我们对38个已鉴定的SNP进行了基因分型，但未发现一致性选择的有力证据——仅先前鉴定的候选SNP中的一种接合子类型与交配状态存在关联，且其所有基因型均未与交配状态相关联。不过，候选SNP整体呈现出较非候选标记更低水平的空间遗传结构。我们还对部分鸟类样本的禽疟感染率进行了统计。结果显示，在采样当年，感染禽疟寄生虫的雄性个体的交配成功率低于未感染个体。由此可见，寄生虫感染及其与特定基因的互作或可影响雄性在求偶场中的交配表现。