关键词: 牛; CXCR1基因; 单核苷酸多态性; 优势等位基因

Abstract: The single nucleotide polymorphisms (SNPs) within the chemokine receptor CXCR1 gene in Holstein cattle，Luxi Yellow cattle and Bohai Black cattle were investigated by DNA sequencing technology，nested-PCR and CRS-PCR methods.Sequencing results showed that four SNPs in exon 2 were identified，which they were 291 bp (C/T)，333 bp (C/T)，337 bp (A/G) and 365 bp (C/T).The value of polymorphism information content indicated(0.25＜PIC＜0.5) that all the four SNPs were moderate polymorphism in Holstein cattle,Luxi Yellow cattle and Bohai Black cattle.Fur
thermore，C, C， A and C predominan allele were identical at 291 bp (C/T)，333 bp (C/T)，337 bp (A/G) and 365 bp (C/T)，with the allelic frequencies 0.82/0.67/0.65，0.80/0.74/0.71，0.70/0.65/0.82，0.56/0.58/0.56 respectivly. Chi-square test indicated all the sites of Bohai Black cattle were in accordance with the Hardy-Weinberg equilibrium，while Holstein cattle meet Hardy-Weinberg equilibrium (P>0.05) at 291 bp (C/T)，333 bp (C/T) and 337 bp (A/G)，and the Luxi Yellow cattle meet Hardy-Weinberg equilibrium only at 365 bp (C/T).

Key words: Bos taurus; CXCR1 gene; single nucleotide polymorphisms (SNPs); predominan allele