Abstract
BACKGROUND: The phagolysosomal function of alveolar macrophage
against M. tuberculosis infection is influenced by Nramp1,
which is encoded by the NRAMP1 gene. There are several genetic
polymorphisms in NRAMP1, and these polymorphisms affect the innate
host resistance through the defect in production and function of Nramp1.
To investigate this relationship, we determined the NRAMP1 genetic
polymorphism in patients with primary tuberculous pleurisy was determined.
METHODS : 56 Fifty-six primary tuberculous pleurisy patient (,) who
were diagnosed by pleural biopsy(,) were designated to the pleurisy
group and 45 healthy adults were designated to the healthy control group.
3 Three genetic polymorphisms of NRAMP1 (,) such as a single point mutation
in intron 4(469+14G/C, INT4), a nonconservative single-base
substitution at codon 543 that changes aspartic acid to asparagine(D543N)
and a TGTG deletion in the 3' untranslated region(1729+55del4, 3'UTR)(,)
were determined. Polymerase chain reaction(PCR) and polymerase chain
reaction-restriction fragment length polymorphism(PCR-RFLP) were used.
RESULTS: The frequencies of mutanat mutant genotypes of INT4 and 3'UTR
were significantly high in pleurisy group(p=0.001, p=0.023). But the
frequencies of D543N were not significantly different between the both
two groups(p=0.079). Odds The odds ratios(,) which are a comparison with
wild genotype for determining mutant genotypes(,) were 8.022(95% confidence
interval=2.422 ~26.572) for INT4 and 5.733(95% confidence interval=1.137 ~28.916)
for 3'UTR which were ;these were statistically significant. But the odds
ratio for D543N was not significant. In the combined analysis of the INT4
and 3'UTR polymorphisms, as compared with GG/++ homozygotes, (delete) the
odds ratios were 6.000(95% confidence interval=1.461 ~ 24.640) for GC/++ genotype
and 14.000(95% confidence interval=1.610 ~121.754) for GC/+del when compared with
GG/++ homozygotes which ;these were statisticallysignificant.
CONCLUSION: Among the NRAMP1 genetic polymorphisms, a single point
mutation in intron 4(469+14G/C, INT4) and a TGTG deletion in the 3' untranslated
region(1729+55del4, 3'UTR) were closely related to the primary tuberculous pleurisy.