ABSTRACT
The mannose-binding lectin gene (MBL2) has also been considered as a possible host response gene in tuberculosis. In Gambia, the frequency of the MBL2 codon 57 mutation was lower in 397 adults with smear-positive pulmonary tuberculosis than in controls (28 versus 33 percent, P 0.04).74 This potentially protective effect of an MBL2 polymorphism was also demonstrated for the G54D mutation in a South African population with pulmonary tuberculosis: the G54D allele was found in 12 of 91 affected subjects (13 percent) and in 22 of 79 TB-negative controls (28 percent; P 0.02).75 A reverse effect was demonstrated in a study in India, in which nearly 11 percent of the 202 subjects with pulmonary tuberculosis but only 2 percent of 109 controls were homozygous for one of the three functional polymorphisms (P 0.008; OR 6.5).76 The frequency of all three variant alleles, particularly the G54D allele, was also greater in the subjects with tuberculosis than in the normal controls. These results, conflicting as they are, may well be confounded by factors related to the comparability of the controls, in societies with considerable ethnic/racial differences and admixturing.
