Insights into the genetic architecture of morphological traits in two passerine bird species
Insights into the genetic architecture of morphological traits in two passerine bird species
复制标题
深入了解两种雀形目鸟类形态特征的遗传结构
作者：
Catarina N. S. Silva;S. McFarlane;Ingerid J. Hagen;Lars Rönnegård;Lars Rönnegård;A. Billing;Thomas Kvalnes;Pentti Kemppainen;Bernt Rønning;T. H. Ringsby;B. Sæther;A. Qvarnström;Hans Ellegren;Henrik Jeldtoft Jensen;A. Husby;A. Husby
要了解和预测进化动态，需要了解表型性状的潜在遗传结构。然而，因果基因座的数量、影响的大小和在基因组中的位置在很大程度上仍然是未知的。在这里，我们使用来自家雀和领蝇的两个大规模数据集的基因组范围的单核苷酸多态(SNP)数据来检查不同形态特征(脚踝长度、翼长、体质量、喙深、喙长度、总和可见徽章大小和白色翼斑)的遗传结构。根据SNPs计算的关联度来估计基因组遗传力。在给定标记密度的情况下，家雀中的SNPs(基于SNP的遗传力)捕获的变异比例低于颈捕蝇者(家雀中有6348个 ，而领苍蝇中有38个SNPs，689个SNP)。事实上，在向下抽样到相似的SNP密度和样本量后，这一估计在物种之间不再有明显差异。染色体分割分析表明，在某些性状上，每条染色体解释的变异比例与染色体大小显著正相关，一般来说，较大的染色体往往比较小的染色体按比例解释更多的变异。最后，我们发现了两个全基因组范围的显著关联，它们的效应大小非常小。20号染色体上的1个SNP与家雀的体长有关，可解释1.2%的表型变异(Vp)；4号染色体上的1个SNP与领蝇的足长相关(3%)。虽然我们不能排除未检测到的大效应基因座的可能性，但我们的结果表明形态性状是一个多基因基础。
Knowledge about the underlying genetic architecture of phenotypic traits is needed to understand and predict evolutionary dynamics. The number of causal loci, magnitude of the effects and location in the genome are, however, still largely unknown. Here, we use genome-wide single-nucleotide polymorphism (SNP) data from two large-scale data sets on house sparrows and collared flycatchers to examine the genetic architecture of different morphological traits (tarsus length, wing length, body mass, bill depth, bill length, total and visible badge size and white wing patches). Genomic heritabilities were estimated using relatedness calculated from SNPs. The proportion of variance captured by the SNPs (SNP-based heritability) was lower in house sparrows compared with collared flycatchers, as expected given marker density (6348 SNPs in house sparrows versus 38 689 SNPs in collared flycatchers). Indeed, after downsampling to similar SNP density and sample size, this estimate was no longer markedly different between species. Chromosome-partitioning analyses demonstrated that the proportion of variance explained by each chromosome was significantly positively related to the chromosome size for some traits and, generally, that larger chromosomes tended to explain proportionally more variation than smaller chromosomes. Finally, we found two genome-wide significant associations with very small-effect sizes. One SNP on chromosome 20 was associated with bill length in house sparrows and explained 1.2% of phenotypic variation (VP), and one SNP on chromosome 4 was associated with tarsus length in collared flycatchers (3% of VP). Although we cannot exclude the possibility of undetected large-effect loci, our results indicate a polygenic basis for morphological traits.
自然群体中常备遗传变异的全基因组数量性状位点作图的挑战和前景
影响因子：
5.2
作者：
Schielzeth
通讯作者：
Schielzeth