Polymorphisms in CCL5 promoter are associated with pulmonary tuberculosis in northern Spain

To study whether two functional single nucleotide polymorphisms of the CC chemokine ligand 5 (CCL5) gene could affect susceptibility to pulmonary tuberculosis (TB) in a human immunodeficiency virus negative genetically homogeneous population, containing newly diagnosed patients with active disease.

Seventy-six patients with active pulmonary TB (PTB) and 157 healthy control subjects from Cantabria, northern Spain, were genotyped for the CCL5 -403G/A and -28C/G polymorphisms.

The frequency of the CCL5-403G/A and -28C/G promoter polymorphisms were significantly different between patients with active TB and control subjects. Three of the four possible haplotypes were also significantly different. The G/G-C/C diplotype was much more frequent in the healthy control group and the G/G-G/G and A/A-C/C diplotypes were more frequent in patients with PTB.

Our findings indicate that CCL5 may play a role in conferring susceptibility to active PTB. Thus, the -403G and -28C alleles, either separately or combined in the G-C haplotype and the GG/CC diplotype, may be related to protection against PTB. By contrast, the -403A and -28G alleles, the G-G or A-C haplotypes and the G/G-G/G and A/A-C/C diplotypes may confer susceptibility to PTB.