We characterized mitochondrial ATP synthase (ATPase) 6 and 8 genes in Labeo calbasu (Hamilton, 1822) and determined genetic variation in wild populations across the natural distribution in Indian rivers. A total of 206 individuals were sampled from 11 riverine sites belonging to distinct geographical locations covering five major river basins. Sequencing of 842 base pairs of ATPase 6/8 revealed 21 haplotypes with haplotype diversity ranging from 0.1250 (River Satluj) to 0.8846 (River Bhagirathi). Analysis of molecular variance (AMOVA) of mitochondrial DNA (mtDNA) data revealed significant genetic differentiation among sites (FST = 0.192, p < 0.0001) which was indicative of moderate level of genetic structuring in the wild L. calbasu populations. The patterns of genetic divergence and haplotype network of mtDNA revealed distinct clades present in Indian rivers. The analysis of data demonstrated the potential of ATPase 6/8 genes in determining the genetic diversity and indicated considerable sub-structuring in wild calbasu populations present in different rivers.
Keywords: ATPase 6/8; Labeo calbasu; genetic divergence; mtDNA.