title: Single nucleotide polymorphisms in bovine PRL gene and their associations with milk production traits in Chinese Holsteins.
abstract: Prolactin (PRL) plays a crucial role in the initiation and maintenance of lactation in mammals. In this study, seven PCR fragments representing most important functional domains of PRL gene were screened for single nucleotide polymorphisms (SNPs) in Chinese Holsteins by single-strand conformation polymorphisms and amplicons sequencing, and their genetic effects on milk production traits were evaluated. A total of four SNPs, including two in the promoter (-1043A>G and -402A>G), one in intron 1 (+2723C>T) and one in exon 4 (+8398G>A) were identified in PRL gene. Statistical results showed significant associations between the promoter genotypes and the milk performance traits in Chinese Holsteins. Cows with genotype P1-GG showed higher milk yields (P < 0.01), while cows with genotype P1-AA showed higher fat contents (P < 0.01). Haplotype analysis of two SNPs in promoter region revealed that the Hap(AG) was significantly associated with increased milk yields and Hap(AA) was associated with increased fat contents (P < 0.01). This is the second study reporting SNPs in the 5'-regulatory region of PRL gene, which interfere with milk production traits.
authors.affiliation: Institute of Cellular and Molecular Biology, School of Life Sciences, Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, Xuzhou Normal University, Xuzhou, China. lajand@126.com
authors.forename: Aijun
authors.initials: A
authors.lastname: Lü
authors.forename: Xiucai
authors.initials: X
authors.lastname: Hu
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
authors.forename: Jihong
authors.initials: J
authors.lastname: Jiang
authors.forename: Chunlei
authors.initials: C
authors.lastname: Zhang
authors.forename: Haixia
authors.initials: H
authors.lastname: Xu
authors.forename: Xueyuan
authors.initials: X
authors.lastname: Gao
mesh_terms: D000818:Animals; D002417:Cattle / Q000235:genetics*; D002681:China; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D056426:Genetic Loci / Q000235:genetics; D006239:Haplotypes / Q000235:genetics; D007774:Lactation / Q000235:genetics*; D008892:Milk / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D018807:Polymorphism, Single-Stranded Conformational; D011388:Prolactin / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D019655:Quantitative Trait, Heritable
chemical_list: D011388:Prolactin