Development and validation of SNP genotyping assays to identify genetic sex in the swimming crab Portunus trituberculatus

The swimming crab Portunus trituberculatus is an economically vital aquaculture species in China and South East Asia. Monosex female culture has been identified as a key priority due to their increased market value, consumer preference and enhanced growth performance. However, the lack of a rapid and reliable sex-linked marker panel has hampered the application of sex control and understanding of the sex determination in the species. In this study, two sex-linked SNPs obtained from our simplified genomic data were validated by sequencing and then converted into competitive allele-specific PCR assays. The results showed high consistency between the genetic and phenotypic sex providing therefore a rapid test sex identification. Moreover, heterogametic genotypes in males provided a significant genetic evidence to support an XX/XY sex determination system in the P. trituberculatus.

Automated summary

The study validated two sex-linked SNPs from simplified genomic data, providing a rapid test for sex identification in Portunus trituberculatus, and revealed significant genetic evidence from heterogametic genotypes in males supporting an XX/XY sex determination system.