Data from: Cytochrome P450 gene Cyp337 and heritability of fitness traits in the Glanville fritillary butterfly

Fitness-related life history traits often show substantial heritable genetic variation in natural populations, but knowledge of the genetic architecture of these traits is limited. In the Glanville fritillary butterfly, we measured the heritability of key life history traits in a large outdoor population cage during two years and generations, and combined this experiment with an association study of a set of candidate genes. The genes were selected on the basis of previous genomic and transcriptomic studies and have been linked to the physiology and life history of this or other arthropod species. Heritability was high and significant for two traits, post-diapause larval development time (h2 = 0.37) and lifetime egg (and larval) production (h2 = 0.62); the latter is closely related to lifetime reproductive success and therefore fitness. We discovered a strong association between genetic polymorphism in the Cytochrome P450 gene Cyp337 and lifetime egg production, which accounted for 14% of the additive variance in egg production. This gene belongs to a group of Cytochrome P450 genes that have a well-documented role in host plant adaptations in Lepidoptera and other insects, and is likely to play an important role in the ecology and microevolution of the Glanville fritillary. This study provides a prime example of a gene associated with heritable fitness variation, measured under semi-natural ecological conditions.

与适合度相关的生活史性状在自然种群中通常存在显著的可遗传遗传变异，但目前对这类性状的遗传结构的认知仍较为有限。本研究以格兰维尔蛱蝶（Glanville fritillary butterfly）为研究对象，在两年的时间跨度与多代周期内，于大型室外种群笼中测定了关键生活史性状的遗传力，并将该实验与一组候选基因的关联分析相结合。这些候选基因是基于既往基因组学与转录组学研究筛选得到的，且已被证实与该物种或其他节肢动物的生理机能及生活史相关。研究发现，两项性状的遗传力较高且具有统计学显著性：分别为滞育后幼虫发育时长（h²=0.37）与终身产卵（及幼虫）量（h²=0.62）；其中后者与终身繁殖成功率密切相关，进而关联到个体适合度。我们发现细胞色素P450（Cytochrome P450）基因Cyp337的遗传多态性与终身产卵量之间存在强关联，该位点可解释产卵量14%的加性遗传方差。该基因隶属于一类细胞色素P450基因家族，这类基因在鳞翅目（Lepidoptera）及其他昆虫的寄主植物适应性中已有充分文献记载其作用，因此可能在格兰维尔蛱蝶的生态与微进化过程中发挥重要作用。本研究为在半自然生态条件下测定的、与可遗传适合度变异相关的基因提供了一个典型范例。