Polymorphism in various genes that may influence susceptibility to tuberculosis (TB) was examined in 46 TB patients and 119 healthy tuberculin-positive controls in Zambia. The odds of having TB was 2.8-fold higher in carriers of the -2518 AG single-nucleotide polymorphism in the promoter region of the CC-chemokine ligand 2 than in those carrying the homozygous genotype AA (95%CI 1.3-5.5).