Sequence variations in the bovine growth hormone gene characterized by single-strand conformation polymorphism (SSCP) analysis and their association with milk production traits in Holstein
1996
Yao, J. | Aggrey, S.E. | Zadworny, D. | Hayes, J.F. | Kuhnlein, U.
Sequence variations in the bovine growth hormone (GH) gene were investigated by single strand conformation polymorphism (SSCP) analysis of seven amplified fragments covering almost the entire gene (2.7 kb). SSCPs were detected in four of these fragments and a total of six polymorphisms were found in a sample of 128 Holstein bulls. Two polymorphisms, a T replaced by C transition in the third intron (designated GH4.1) and an A replaced by C transversion in the fifth exon (designated GH6.2), were shown to be associated with milk production traits. GH4.1c/GH4.1c bulls had higher milk yield than GH4.1c/GH4.1t (P less than or equal to 0.005) and GH4.1t/GH4.1t (P less than or equal to 0.0022) bulls. GH4.1c/GH4.1c bulls had higher kg fat (P less than or equal to 0.0076) and protein (P less than or equal to 0.0018) than GH4.1c/GH4.1t bulls. Similar effects on milk production traits with the GH6.2 polymorphism were observed with the GH6.2a allele being the favorable allele. The average effects of the gene substitution for GH4.1 and GH6.2 are similar, with +/-300 kg for milk yield, +/-8 kg for fat content and +/-7 kg for protein content per lactation. The positive association of GH4.1c and GH6.2a with milk production traits may be useful for improving milk performance in dairy cattle.
显示更多 [+] 显示较少 [-]