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bioRxiv · 10.1101/2024.01.23.576732

Selection of different parameters to study epistatic effect between heat shock and slightly deleterious mutations in the most fragile stage of embryogenesis Cyprinus carpio L.

Abstract

The primary genetic challenge encountered in artificial populations lies in the strong genetic drift, which leads to the accumulation of numerous slightly deleterious mutations across the genome. Such mutations diminish the adaptability of the entire population. The objective of this project involves the investigation and implementation of genetic selection methods within cultivated fish populations such Cyprinus carpio L. In order to maintain a high level of genome quality in productive species, we conducted a proof-of-principle experiment employing stress-induced strong purifying selection. This selection process is based on negative epistasis and effectively eliminates organisms carrying an excess of deleterious variants. The first step involves the creation of mutant and intact groups of fish. To obtain mutant groups, we treated male gametes with the ENU mutagen, which primarily induces single-nucleotide substitutions uniformly throughout the genome, thereby imitating natural mutations. This methodology is paramount for the accurate interpretation of experimental outcomes. Notably, temperature stands as a pivotal factor influencing the embryonic development of fish. Therefore, we subjected the embryos to a diverse range of temperatures and varied the duration of exposure during critical stages of embryogenesis. Through meticulous examination, we ascertained that the stage most susceptible to screening purposes is the 22-somite pair stage, occurring at a temperature of 38{degrees}C, with a 40-minute exposure period. We suppose, this comprehensive approach can be applied to improve the quality of the gene pool within domestic fish populations, ultimately enhancing the economic efficacy of fish farms. The future prospects of this method encompass its potential application to various species.

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BibTeXRIS

Kuzmin, A. V., Skripskaya, V., Lobanova, V., Brodovaya, P., Tarasova, A., Mukhitov, M., Popadin, K., Mikhailova, A. G., Vinogradov, E., Mugue, N., Balashov, D.. 2024-01-25. Selection of different parameters to study epistatic effect between heat shock and slightly deleterious mutations in the most fragile stage of embryogenesis Cyprinus carpio L.. https://doi.org/10.1101/2024.01.23.576732

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