Chinese Scientists Discover First Sex-Determining Gene Pangu in Cyprinid Fish

Chinese researchers have identified the first primary sex-determining gene in cyprinid fish, naming the new gene pangu after the mythological figure associated with creation and male strength, jfdaily.com reported.

The Discovery of the Pangu Gene in Yellow River Carp

The findings were published in the international journal Science Advances on October 10, 2026. Animal sex determination is a core question in evolutionary biology, and fish exhibit nearly all vertebrate sex-determination types. Cyprinid fish represent the most diverse and widespread freshwater fish group globally, holding a vital position in species origin and biological evolution.

However, cyprinid fish have experienced extra whole-genome duplications, creating complex polyploid genomes that make identifying sex-determining genes extremely challenging. Until now, no functionally confirmed sex-determining genes had been reported in cyprinid fish. Establishing a sex-determining gene requires strict scientific standards, including sex-specific genetic characteristics, spatiotemporal expression during the critical sex-determination window, and complete evidence chains of loss-of-function and gain-of-function leading to sex reversal.

Genetic Evidence and Molecular Mechanisms of Carp Sex Reversal

Following a decade of exploration using genomic and population genomic re-sequencing, the research team screened a male-specific DNA fragment and isolated the coding gene pangu from it. Research showed that pangu displays male-specific expression during early testis differentiation in male carp. Knocking out pangu in male carp triggers a sex reversal from male to female, while expressing pangu in female carp induces a sex reversal from female to male.

The characteristics of pangu meet the golden standard for identifying primary sex-determining genes, confirming it as the primary sex-determining gene in Yellow River carp. The study further revealed that the molecular mechanism by which pangu determines sex likely operates through suppressing the cyp19a1a-mediated female differentiation pathway.

Conservation of the Pangu Gene Across Carp Species

The research team also identified pangu and its conserved male sex-determining function in other cyprinid species, including red carp, koi, and German mirror carp. These findings suggest that pangu may serve as a shared primary sex-determining gene across the genus Cyprinus.

Academician He Shunping and other experts provided guidance and assistance for the research work.

The identification of pangu provides foundational insights for clarifying animal sex-determination mechanisms following complex genome duplication events.