Genetic diversity and taxonomic status of Gymnocypris chilianensis based on the mitochondrial DNA D-loop region

To analyse the genetic diversity and
taxonomic status of Gymnocypris chilianensis,
D-loop region of the mitochondrial DNA
was sequenced in 50 individuals of G.
chilianensis obtained from two geographic locations (Heihe
River and Shule River) and 25 individuals of G. przewalskii. These samples were analyzed for genetic
diversity and sequence divergence, and 25 homologous sequences of another
affinity G. eckloni downloaded from
GenBank were analyzed. The results revealed that G. chilianensis of the Shule River showed lower haplotype diversity
(Hd = 0.963) as well as nucleotide diversity (Pi = 0.00414) than the other
populations, indicating that G.
chilianensis of the Shule River should be protected
preferentially due to its lower level of genetic diversity. The
study also demonstrated the genetic distance of G. chilianensis in both Heihe River and Shule River was 0.0013,
and the genetic distances between the aforementioned two populations and the G. przewalskii were 0.0143
and 0.0137, respectively. The genetic distances between the two G. chilianensis populations and the G. eckloni were 0.0148 and 0.0141,
respectively. The NJ phylogenetic trees showed that G. chilianensis had further genetic distance with G. eckloni and G. przewalskii. Therefore, G.
chilianensis could be considered as an independent species of Gymnocypris.