Polymorphism Of Bovine TNF-A Gene,AHCY Gene And There Associations With Mastitis In Chinese Holstein Cows

Four hundred and seven Chinese Holstein cows were chosen and divided into 2 groups (controly group (317), sub-clinical and clinical group (100)) to investigate variations in bovine tumor necrosis factor-alpha (TNF-a) gene and S-adenosylhomocysteine hydrolase encoding gene and analyze their associations with mastitis. The aim of testing TNF-a and AHCY genes′genetic diversity and finding some genetic markers which associated with cow mastitis was to lay the root for develop dairy cattle breed which have the breast tissue resistant trait, and reduce the incidence of breast tissue and reduce its damage to the dairy industy. Ten polymorphic sites were detected (including 7 SNPs in 5′UTR and 2 SNPs in Exon2 of TNF-a gene, the embody number of GeneBank is GU129693; 1 SNP in 3′UTR of AHCY gene). The resμLts were showed as follows:G→A mutation at 39 bp in exon2 and one C→T mutation at 293 bp in exon4, and C→G mutation in 5′UTR were detected. The three polymorphic sites can be cut by DraI, AfaI and DdeI restriction enzymes respectively, the DraI locus was create restriction enzyme cutting Site. The further analysis of the mutant sites showed that the distribute of A,B allele frequency was uneven in DraI site, but it was uniform in AfaI and DdeI sites. In the three sites, the polymorphism information content (PIC) was different, it was low polymorphism in DraI site (PIC<0.25), it was moderate polymorphism in AfaI and DdeI sites (0.25