Effect of Polymorphism in FGF2 Gene on First Lactation Milk Yield and Milk Composition Traits in Karan-Fries Cattle

Abstract

The present study was performed to investigate the polymorphisms in the Fibroblast Growth Factor 2 (FGF2) gene and to reveal the association of different genotypes corresponding to gene with Breeding Value (BV) for first lactation milk yield and milk composition traits of Karan Fries (HF crossbred) cattle. The traits were adjusted against the significant effect of non-genetic factors. Blood samples were collected on vacutainer tubes supported with EDTA to prevent blood Clotting and DNA samples were isolated and purified using standard phenol chloroform method. Polymerase chain reactions were performed using specific primers for gene under study. FGF2 gene PCR products were subjected to cut them with specific restriction enzyme: Csp6I. Polymerase Chain Reaction – Restriction Fragment Length Polymorphism (PCR-RFLP) analysis of FGF2 (intron 1) gene revealed three genotypes; GG (171bp), AG (207bp and 171bp,) and AA (207bp). Genotypic frequencies of GG, AG and AA were 0.31, 0.52 and 0.17 whereas the allelic frequencies for G and A allele were 0.57 and 0.43, respectively. Breeding value of GG genotype was highest for ATDMY(kg) and 305MY (kg) (11.21 ± 0.67 and 3172.01 ± 51.33 ) whereas, AA genotype had highest breeding value for ATDFP and LFY (4.39 ± 0.16 and 137.41 ± 5.76). In addition, no significant effect of polymorphism on any of the traits was found. GG genotype was associated with a higher breeding value for 305MY, suggesting its further research in a large population and consequently its use in gene assisted selection for the genetic improvement of milk production.