Monocyte chemotactic protein-1 -2518 gene polymorphism and susceptibility to spinal tuberculosis

Background and aims: Monocyte chemotactic protein-1 (MCP-1) gene polymorphisms play important roles in regulating immunological reactions and may be associated with pulmonary tuberculosis. However, the relationship between the MCP-1 -2518 gene polymorphism and susceptibility to spinal tuberculosis remains unknown. We undertook this study to investigate the relationships between MCP-1 promoter 2518 genotype frequency and allele polymorphisms and susceptibility to spinal tuberculosis in a Chinese Han population.

Methods: Patients with spinal tuberculosis and healthy volunteers were enrolled between December 2004 and December 2010. MCP-1 -2518 polymorphisms in both groups were detected using polymerase chain reaction and DNA sequencing. MCP-1 genotype was analyzed in all patients. Differences in genotype frequencies between groups were compared using χ(2) tests.

Results: A total of 208 patients with spinal tuberculosis and 210 healthy volunteers were included. The distribution frequencies of MCP-1 -2518 GG, GA and AA genotypes were 36.1, 50.9 and 13.0%, respectively, in the case group and 25.2, 53.8 and 21.0%, respectively, in the control group (p <0.05). MCP-1 -2518 GG genotype was significantly associated with the onset of spinal tuberculosis (OR = 2.306, 95% CI = 1.273-4.178). The G and A allele frequencies were 61.5% and 38.5%, respectively, in the case group, and 52.1% and 47.9% in the control group (p <0.05), the allele "G" of MCP-1 -2518 showed an association with an increased risk for spinal tuberculosis: OR = 1.777, 95% CI = 1.053-2999, p = 0.03 in the dominant model; OR = 1.67, 95% CI = 1.097-2.544, p = 0.016 in the recessive model.

Conclusions: The MCP-1 -2518 GG genotype and presence of the G allele may be associated with susceptibility to spinal tuberculosis in the Chinese Han population.