Scussel Sarah, Gaudillat Benjamin, Esnault Jérémy, Lejarre Quentin, Duployer Marianne, Messaoudi Daouia, Mavingui Patrick, Tortosa Pablo, Cattel Julien
Groupement d'Intérêt Public Cyclotron Océan Indien (CYROI), 2 rue Maxime Rivière, 97490 Ste Clotilde, France.
Symbiosis Technologies for Insect Control (SymbioTIC), Plateforme de Recherche Cyroi, 2 rue Maxime Rivière, 97490 Ste Clotilde, France.
Insects. 2023 Jul 13;14(7):630. doi: 10.3390/insects14070630.
The mass production of mosquitoes at an industrial scale requires efficient sex separation, which can be achieved through mechanical, genetic or artificial intelligence means. Compared with other methods, the genetic sexing approach offers the advantage of limiting costs and space by removing females at the larval stage. We recently developed a Genetic Sexing Strain (GSS) in based on the sex linkage of the allele, conferring resistance to dieldrin, to the male (M) locus. It has been previously reported that dieldrin ingested by larvae can be detected in adults and bioaccumulated in predators, raising the question of its use at a large scale. In this context, we performed several experiments aiming at optimizing dieldrin selection by decreasing both dieldrin concentration and exposure time while maintaining a stable percentage of contaminating females averaging 1%. We showed that the previously used dieldrin exposure induced an important toxicity as it killed 60% of resistant males at the larval stage. We lowered this toxicity by reducing the dose and/or the exposure time to recover nearly all resistant males. We then quantified the residues of dieldrin in resistant male adults and showed that dieldrin toxicity in larvae was positively correlated with dieldrin concentrations detected in adults. Interestingly, we showed that the use of reduced dieldrin exposure led to a dieldrin quantification in adult males that was below the quantity threshold of the Gas Chromatography-Mass Spectrometry detection method. Presented data show that dieldrin exposure can be adjusted to suppress toxicity in males while achieving efficient sexing and lowering the levels of dieldrin residues in adults to barely quantifiable levels.
以工业规模大规模生产蚊子需要高效的性别分离，这可以通过机械、遗传或人工智能手段实现。与其他方法相比，遗传性别鉴定方法具有通过在幼虫阶段去除雌性来限制成本和空间的优势。我们最近基于等位基因与男性（M）位点的性连锁开发了一种遗传性别鉴定品系（GSS），该品系赋予对狄氏剂的抗性。此前有报道称，幼虫摄入的狄氏剂可在成虫中检测到并在捕食者体内生物累积，这引发了其大规模使用的问题。在此背景下，我们进行了多项实验，旨在通过降低狄氏剂浓度和暴露时间，同时保持污染雌性的稳定比例平均为1%，来优化狄氏剂筛选。我们发现，之前使用的狄氏剂暴露会导致重要的毒性，因为它在幼虫阶段杀死了60%的抗性雄性。我们通过降低剂量和/或暴露时间来降低这种毒性，以恢复几乎所有的抗性雄性。然后我们量化了抗性雄性成虫中狄氏剂的残留量，并表明幼虫中的狄氏剂毒性与成虫中检测到的狄氏剂浓度呈正相关。有趣的是，我们发现使用降低的狄氏剂暴露导致成年雄性中的狄氏剂定量低于气相色谱 - 质谱检测方法的定量阈值。所呈现的数据表明，可以调整狄氏剂暴露以抑制雄性中的毒性，同时实现高效的性别分离，并将成虫中狄氏剂残留水平降低到几乎无法量化的水平。
