CCL2 and chronic obstructive pulmonary disease: Several studies have shown rs2857656 and rs4586 as MCP-1 functional polymorphisms to affect MCP-1 expression, leading to the susceptibility to pulmonary tuberculosis, spinal tuberculosis, and chronic obstructive pulmonary disease.[13–15] Another functional genetic polymorphism at rs1024611 (-2518 A > G) in the promoter region of MCP-1 gene affects the expression level of MCP-1 and is associated with a variety of inflammatory diseases.