Data from: The comparative landscape of duplications in Heliconius melpomene and Heliconius cydno

Gene duplications can facilitate adaptation and may lead to inter-population divergence, causing reproductive isolation. We used whole-genome re-sequencing data from 34 butterflies to detect duplications in two Heliconius species, H. cydno and H. melpomene. Taking advantage of three distinctive signals of duplication in short-read sequencing data, we identified 744 duplicated loci in H. cydno and H. melpomene, 96% of which were validated with single molecule sequencing. We have found that duplications overlap genes significantly less than expected at random in H. melpomene, consistent with the action of background selection against duplicates in functional regions of the genome. Duplicate loci that are highly differentiated between H. melpomene and H. cydno map to four different chromosomes. Four duplications were identified with a strong signal of divergent selection, including an odorant binding protein and another in close proximity with a known wing colour pattern locus that differs between the two species.

基因重复可促进适应性演化，并可引发种群间分化，最终导致生殖隔离。本研究利用34只蝴蝶的全基因组重测序（whole-genome re-sequencing）数据，对釉蛱蝶属（Heliconius）的两个物种——诗神袖蝶（H. cydno）与红带袖蝶（H. melpomene）——的基因重复事件进行检测。借助短读长测序（short-read sequencing）数据中三类特征性的基因重复信号，本研究在上述两个物种中共鉴定出744个重复位点（duplicated loci），其中96%经单分子测序（single molecule sequencing）验证。研究发现，红带袖蝶的基因重复与基因区域的重叠程度显著低于随机预期，这与基因组功能区域内针对重复序列的背景选择（background selection）作用相符。诗神袖蝶与红带袖蝶间分化程度极高的重复位点，分布于四条不同的染色体上。本研究还鉴定出4个带有强烈歧化选择（divergent selection）信号的重复位点，其中包括一个气味结合蛋白（odorant binding protein）基因，以及另一个紧邻已知的两物种间差异翅色模式位点的重复位点。