Background: Genetic factors play an important role in the development of disease susceptibility
or protection. Cytokine gene polymorphisms are reported to be associated with altered levels
of cytokine production that can impact disease progression in HIV and TB.
Objective: In this study, we studied IL-10 -592(C/A) and TGF-β -509 (C/T) promoter polymorphisms
to understand their role in susceptibility or resistance to HIV and TB in a South Indian population.
Method: Genomic DNA was isolated from healthy controls, pulmonary tuberculosis patients (n=122)
and HIV positive individuals (n=100) and used for genotyping by polymerase chain reaction followed
by restriction fragment length polymorphism (PCR-RFLP) method.
Results: Results revealed that under dominant model (CC vs CA+AA), IL-10 -592 ‘A' allele either
‘CA' or ‘AA' combinations significantly associated with susceptibility to HIV compared to healthy
controls (OR: 1.88(1.05-3.35); p=0.030). However, we found no significant association with TB.
TGF-β -509 polymorphism did not associate with either HIV or TB under overdominant model. Neither
of the promoter polymorphisms associated with sex in either HIV or TB. However, a trend towards
higher risk to HIV was found in females compared with males in IL-10 -592 ‘AA' genotype.
Conclusion: This study suggests the association of IL-10 -592 “AA” genotype with susceptibility to
HIV under dominant model in the Southern Indian population. Future studies are needed with a larger
sample size in order to confirm the observations made in this study.