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Genetic variation in the OPN gene affects milk composition in Chinese Holstein cows
Sayed Haidar Abbas Raza1, Rajwali Khan2, Sameer D Pant3
1College of Animal Science and Technology, Northwest A&F University, Yangling, China.
Abstract:
The aim of this study was to investigate the association between genotypes and haplotypes of OPN, and milk composition in dairy cows. A total of 317 Chinese Holstein cows were genotyped via DNA sequencing in this study. Three single nucleotide polymorphisms (SNPs), g.2916G > A, g.58675C > T and g.58899C > A, and eight haplotypes were identified. Of the eight possible haplotypes, four haplotypes i.e., Hap2 (ACC; 55.30%), Hap6 (GCC, 15.6%), Hap1 (ACA, 13.6%) and Hap4 (ATC, 5.70%), were considered to be major with a cumulative estimated frequency of >90%. Single markers (g.2916G > A and g.58899C > A) and Haplotype Hap6/4 were found to be associated with an increase in butter-fat percentage (p < 0.05). Taken together, our results provided evidence that polymorphisms in OPN are associated with milk composition, and could potentially be used for marker-assisted selection in Chinese Holstein cows.
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