Sequence characterization and polymorphism detectionin AQP7 gene of Murrah buffalo
Aquaporin 7 (AQP7) gene is a member of aqua-glyceroporins which transports glycerol and water to spermatids. The present study aimed to investigate the polymorphisms within exons 2, 3, 4, 5 and their flanking intronic regions in AQP7 gene of Murrah bulls. Genomic DNA was extracted from 69 Murrah bulls blood samples and was subjected to polymerase chain reaction- single strand conformation polymorphism (PCR-SSCP) analysis. PCR-SSCP analysis revealed a total of eight different variants for amplicons of exons 4 and 5. Amplicon of exon 4 revealed three different patterns viz. E4P1, E4P2 and E4P3 with the frequency of 0.30, 0.22 and 0.48, respectively. Analysis of exon 5 revealed five unique SSCP patterns viz. E5P1, E5P2, E5P3, E5P4 and E5P5, with the frequency of 0.10, 0.37, 0.20, 0.20 and 0.13, respectively. Sequence analysis showed 16 single nucleotide polymorphisms, 7 of which were observed in coding region. Amplicons of exons 2 and 3 showed monomorphic patterns. However, compared to the reference sequence of taurine cattle one transition (C6878T) in exon 3 and 4 transitions (G2099A, C2116T, A2117G, G6848C) in intron 2 were observed for all the bulls under study. The genetic variability identified in the AQP7 gene may serve as potential genetic marker(s) for semen quality traits in buffalo.