Novel association between polymorphism of the AQP3 gene and milk production traits in Bos indicus

Abstract

Aquaporins are protein channels that passively transport the water in or outside the cells according the water potential gradient. Functions of aquaporin proteins are regulated by different AQP gene members. The present novel experimentation investigates polymorphism in AQP3 gene in indigenous (Rathi) breed of cattle and its association with different milk production traits. The study was performed on 104 Rathi cattle of LRS farm, RAJUVAS, Bikaner. DNA isolated from these samples were amplified by PCR using manually designed specific primers for 367 bp long fragment of exon 6 of AQP3 and subjected to Single Strand Conformation polymorphism (SSCP) analysis. Two genotypic patterns GC and GG were obtained by modified Sanger’s di deoxy sequencing method. The genotypic frequencies of GC and GG were 0.90 (n=94), 0.10 (n=10) respectively. Gene frequencies for G and C were 0.55 and 0.45 respectively. The calculated genotypic frequency indicated that GG genotype is predominant in Rathi cattle. Analysis of variance (ANOVA) of linear model for dependent variable was non-significant (p> 0.05) for MY (Milk yield), LL (lactation length); significant for PDMY (per day milk yield) (p≤ 0.05) and highly significant for PMY (peak milk yield) (p≤ 0.01) in Rathi cattle at 5% level significance. It was also observed that PDMY, PMY and MY were higher for genotype GG than the genotype GC. Obtained results could open new possibilities to define AQP3 as candidate gene for their functional specificity to control the important economic traits related to the milk production in cattle.