Molecular characterization of lactoferrin gene and its association with mastitis in crossbred cattle

Genomic DNA was isolated from the blood of 100 crossbred cattle (HF, Jersey, Brown Swiss x Hariana cattle). Exon 4 and intron 6 of lactoferrin (Lf) gene was characterized by PCR-SSCP. Two alleles of exon 4, namely E & F showing two genotypes EE and EF and two alleles of intron 6, namely A and B showing two genotypes AA and AB were found in studied population. Cloning and sequencing results revealed that in exon 4, there was one SNP in allele E and two SNPs in allele F, which changed amino acid isoleucine to valine. In intron 6 there was one SNP in allele A and three SNPs in allele B. Least square analysis for SCC and FLMY revealed that genotype AA was significantly associated with low SCC, while genotype AB was significantly associated with high SCC. However, genotype EE was significantly associated with FLMY as compared to genotype EF.