Polymorphisms Of Equine MxA Gene

In the present research, extract cDNA of MxA protein from single nucleotide cell of horse external circle blood from Hokkaido, Taishu, Miyako, Thoroughbred, Arab, Breton, Criollo, Perceron horses. The polymorphisms of nucleotide sequence can be analyzed through DNA sequence analysis of recombinant actor. As the result, there are sense mutations in three base sites of horse MxA cDNA complete sequence: A replaced G at 977 site, A replaced T at 1234 site and C replaced G at 1790 site. We can make a conclusion that the replacements of base pairs caused Lys replaced Arg at 298 site, Val→Glu at 377 and Trp→Cys at 562 site .In these three mutation sites mentioned above, we discovered that at 977site G→A and at 1234site T→A appeared in all nine breed we examined, plus, didn't find differences between the breeds, but at 1790 site G→C has breed differences. Therefore we adopted the mismatch primer restriction fragment length polymorphisms method to examine the polymorphism of 3'region(1790 site cDNA) the 12th exon of MxA gene. The result showed the mutation at this site depends on the differences between the individual. There were G\G, C\C and C\G types; most were C\G type, no breeding characteristics.