Whole‐genome resequencing reveals novel sex‐related markers and candidate gene in the Chinese soft‐shelled turtle (Pelodiscus sinensis)

Abstract

An apparent sexual dimorphism, such as growth rate and immunocompetence, is observed in the Chinese soft‐shelled turtle (Pelodiscus sinensis). The identification of sex‐related markers and candidate genes holds significance for the sex‐controlled breeding of P. sinensis. In this study, through an integration of whole‐genome resequencing and Sanger sequencing, 21 female‐specific single nucleotide polymorphisms (SNPs) were identified. Based on these SNPs, the rapid and cost‐effective molecular methodologies for genetic sex identification in P. sinensis were established. Of note, 19 validated SNPs are located within the zinc and ring finger 3 (ZNRF3) gene, which has been reported to be testis‐determining in mammals. Cloning of the ZNRF3 gene from P. sinensis (PsZNRF3) and analysis of its expression profile in tissues and in response to sex steroid hormone treatment demonstrated exhibiting a female‐biased expression pattern. These findings not only provide molecular markers for sex‐controlled breeding in P. sinensis but also open up a solid basis for revealing the sex‐determination mechanism of this species.