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）在可持续、高效防控昆虫害虫领域具备巨大应用潜力。此类策略通过野外释放转基因昆虫（transgenic insects），旨在将工程化等位基因（engineered alleles）永久或瞬时引入野生种群中。若转基因相关适合度成本（transgene-associated fitness costs）降低了释放昆虫的相对表现，则该策略的防控效力会随之下降。本研究提出一种量化转基因相关适合度成本的方法：在重复笼养种群中，使转基因与野生型等位基因（wild-type alleles）展开竞争，进而分析其进化轨迹。借助该方法，我们估算了小菜蛾（diamondback moth）与橄榄实蝇（olive fly）中两种可抑制雌性致死转基因（repressible female-lethal transgenes）的终生适合度成本，结果显示该成本处于野外防控项目可接受的范围之内。此外，基于基因型水平适合度成本（genotype-level fitness costs）的估算值，我们得以对所研究转基因的长期进化轨迹进行预测。上述预测结果表明：即便工程化致死性（engineered lethality）受到抑制，转基因相关适合度成本最终仍将导致这些转基因完全消亡，但在此之前它们可在不同时长内持续存续于种群中。这意味着在这些品系（strains）中，四环素介导的转基因野外存续几乎不可能实现；同时也提示，对转基因相关适合度成本的精准估算，可用于野外试验解耦型基因驱动系统组件（uncoupled gene drive system components）。