DNA Polymorphisms at Candidate Gene Loci and Their Relation with Milk Production Traits in Murrah Buffalo (<i>Bubalus bubalis</i>)

Abstract

DNA polymorphism within diacylglycerol transferase 2 (DGAT2) / monoacyl glycerol transferases 2 (MOGAT2), leptin and butyrophilin genes were analysed using PCR-SSCP in Murrah buffalo. The single strand conformation polymorphism (SSCP) analysis of amplified gene fragment in exon 5 of MOGAT2, exon 3 of leptin and intron 1 of butyrophilin gene revealed different patterns. A, B and C showed the following frequencies for each candidate gene in 53 (A=0.49, B=0.36 and C=0.15), 65 (A=0.38 and B=0.62) and 55 samples (A=0.6, B=0.31 and C=0.09) from Murrah buffaloes, respectively. The strand conformation polymorphism (SSCP) followed by DNA sequencing revealed one single nucleotide polymorphism (SNP) that was (c.193T>C) in MOGAT2, one single nucleotide polymorphism (SNP) (c.25 T>C) in leptin and one single nucleotide polymorphism (SNP) (c.184C>T>G) in butyrophilin gene confirmed BTI1 SSCP.The statistical analysis using general linear model procedure for association study, indicated that Murrah buffalo monoacyl glycerol transferases 2 (MOGAT2)(c.193T>C) single nucleotide polymorphism (SNP)and (c.25 T>C) in leptingenotypes were not significantly different (P>0.01) in Murrah buffalo for milk production traits milk yield, fat percentage and single nucleotide polymorphism (SNP)percentage. However, the statistical analysis for association study indicated BTI1 SSCP was significantly (P≤0.05) associated with 305-days lactation milk yield. The Murrah buffaloes with BTI1BB genotypes had 683.93 kg and 320.48 kg higher milk yield as compared to BTI1AA and BTI1CC genotypes, respectively. The positive association of butyrophilin single strand conformation polymorphism (SSCP) polymorphism with milk yield will be a useful tool for future selection and breeding strategies and genetic improvement of buffaloes for milk yield.