Data from: Population-level effects of fitness costs associated with repressible female-lethal transgene insertions in two pest insects

Genetic control strategies offer great potential for the sustainable and effective control of insect pests. These strategies involve the field release of transgenic insects with the aim of introducing engineered alleles into wild populations, either permanently or transiently. Their efficacy can therefore be reduced if transgene-associated fitness costs reduce the relative performance of released insects. We describe a method of measuring the fitness costs associated with transgenes by analyzing their evolutionary trajectories when placed in competition with wild-type alleles in replicated cage populations. Using this method, we estimated lifetime fitness costs associated with two repressible female-lethal transgenes in the diamondback moth and olive fly as being acceptable for field suppression programs. Furthermore, using these estimates of genotype-level fitness costs, we were able to project longer-term evolutionary trajectories for the transgenes investigated. Results from these projections demonstrate that although transgene-associated fitness costs will ultimately cause these transgenes to become extinct, even when engineered lethality is repressed, they may persist for varying periods of time before doing so. This implies that tetracycline-mediated transgene field persistence in these strains is unlikely and suggests that realistic estimates of transgene-associated fitness costs may be useful in trialing ‘uncoupled’ gene drive system components in the field.遗传防控策略（genetic control strategies）为可持续且高效地防控昆虫害虫提供了巨大潜力。此类策略通过野外释放转基因昆虫（transgenic insects），以期将工程化等位基因永久或暂时性地引入野生种群。若转基因相关适合度成本（fitness cost）降低了释放昆虫的相对适合度，则会削弱此类策略的防控效果。 我们开发了一种量化转基因相关适合度成本的方法：通过在重复笼养种群（replicated cage populations）中，将转基因等位基因与野生型等位基因（wild-type alleles）置于竞争环境下分析其演化轨迹，以此测算转基因相关的适合度成本。利用该方法，我们估算出小菜蛾（diamondback moth）及橄榄蝇（olive fly）中两种可阻抑雌性致死转基因（repressible female-lethal transgenes）的终生适合度成本，结果表明该成本处于野外种群抑制项目可接受的范围内。此外，借助这些基于基因型的适合度成本估算值，我们能够对所研究转基因的长期演化轨迹进行预测。预测结果显示，尽管转基因相关适合度成本最终将导致此类转基因彻底消亡——即便工程化致死效应被阻抑——但它们仍可在消亡前存续一段长短不一的时间。这意味着在上述品系中，四环素介导（tetracycline-mediated）的转基因野外存续可能性极低，同时也提示，精准估算转基因相关适合度成本，或可用于野外试验“解偶联”基因驱动系统（gene drive system）组件。