Association of NOS2A gene polymorphisms with susceptibility to bovine tuberculosis in Chinese Holstein cattle.

Bovine tuberculosis (bTB) is a global zoonotic disease that has detrimental economic impacts worldwide. The NOS2A gene plays a key role in immunological control of many infectious diseases. However, research on the association between NOS2A polymorphisms and bTB infection in Holstein cattle reared on the Yunnan-Guizhou plateau of China is scarce. This study investigated a possible linkage between NOS2A polymorphisms and risk of developing bTB in Chinese Holstein cattle. The NOS2A gene was genotyped in 144 bTB-infected Holstein cows and 139 healthy controls were genotyped through nucleotide sequencing. Ten single-nucleotide polymorphisms (SNPs) were detected, six of which were associated with susceptibility/resistance patterns of bTB. Furthermore, the C/T genotypes of 671 and 2793, and T/T genotype of E22 (+15) were significantly associated with susceptibility risk; the G/A genotype of 2857, T/T genotype of E9 (+65), and C/C genotype of E9 (+114) probably increased resistance to bTB. In addition, the haplotypes of NOS2A-2 and NOS2A-9 were risk factors for bTB susceptibility, while the NOS2A-5 and NOS2A-8 haplotypes were contributing protective variants against tuberculosis. There is a significant association between variation in SNPs of NOS2A and tuberculosis susceptibility/resistance pattern. These findings suggest that substitution of genetic selection would be helpful for eradicating bTB. However, further investigation is required to study the underlying mechanism through which NOS2A polymorphisms affect bTB infection.

CARD15 Gene Polymorphisms Are Associated with Tuberculosis Susceptibility in Chinese Holstein Cows.

Bovine tuberculosis (BTB) is a significant veterinary and financial problem in many parts of the world. Associations between specific host genes and susceptibility to mycobacterial infections, such as tuberculosis, have been reported in several species. The objective of this study was to identify and evaluate the relationship of single-nucleotide polymorphisms (SNPs) in the CARD15 gene with susceptibility to BTB in Chinese Holstein cows. DNA samples from 201 Chinese Holstein cows (103 cases and 98 controls) were collected from Kunming City, Yuxi City, and Dali City in China. SNPs in the CARD15 gene were assessed using polymerase chain reaction (PCR) and restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). Case-control association testing and statistical analysis identified six SNPs associated with susceptibility to BTB in Chinese Holstein cows. The frequency of genotypes C/T, A/G, A/G, A/G, C/T, and A/G in E4 (-37), 208, 1644, 1648, 1799, and E10 (+107), respectively, was significantly higher in cases than in controls, and also the alleles C, A, A, G, T, and A, respectively, were associated with a greater relative risk in cases than in controls. The distribution of two haplotypes, TGGACA and CAGACA, was significantly different between cases and controls. Overall, this case-control study suggested that E4 (-37)(C/T), 208(A/G), 1644(A/G), 1648(A/G), 1799(C/T), and E10 (+107)(A/G) in the CARD15 gene were significantly associated with susceptibility to BTB in Chinese Holstein cows and that haplotypes TGGACA and CAGACA could be used as genetic markers in marker-assisted breeding programs for breeding cows with high resistance to BTB.