Distribution of single nucleotide polymorphisms in the CXCR1 gene and association with calf diseases in Japanese Black cattle.

The chemokine (C-X-C) receptor 1 (CXCR1) expressed on the neutrophil surfaces interacts primarily with interleukin-8 (IL-8) and has an important role in immune response. Two interesting single nucleotide polymorphisms (SNPs), SNP CXCR1+777G>C and SNP CXCR1-1768T>A, that exhibit an association with subclinical mastitis and milk quality in dairy cattle, respectively, have been reported in the bovine CXCR1 gene. The aim of this study was to demonstrate the presence of the two SNPs in the CXCR1 gene of Japanese Black cattle and examine the association between the SNPs and clinical diseases including intestinal and respiratory diseases in calves. Genotyping of the SNPs in healthy Japanese Black cattle showed that the SNPs were also present in Japanese Black cattle with gene frequencies of 0.37 and 0.15 for the C-type allele in SNP CXCR1+777 and for the A-type allele in SNP CXCR1-1768, respectively. Statistical analysis of the genotype distribution of the SNPs in the bovine CXCR1 gene in healthy and clinical intestinal or respiratory diseased Japanese Black cattle indicated no significant association of the SNPs with clinical diseases in the calves. However, a significant correlation of the number of A alleles in SNP CXCR1-1768 with white blood cell (WBC) and platelet counts was found in the disease group. It is possible that the SNP in the bovine CXCR1 gene plays a role in modulating the hematological profile of WBC and platelet counts.