Lack of Association between IL-10 Gene Promoter Polymorphisms and Susceptible to Tuberculosis in Thai Patients
Manaphol Kulpraneet MD*, Anirut Limtrakul PhD**, Surangrat Srisurapanon PhD***, Piyatida Tangteerawatana PhD**
Affiliation : * Department of Internal Medicine, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand ** Department of Microbiology, Faculty of Medicine, Srinakharinwirot University, Bangkok, Thailand *** Department of Pathology, Faculty of Medicine, Srinakharinwirot University, Bangkok, Thailand
Background : Cytokines play a major role in defense against Mycobacterium tuberculosis infection. Polymorphisms in
the genes encoding various cytokines have been associated with tuberculosis susceptibility. Polymorphisms of the regulatory
cytokine gene, the interleukin (IL)-10 is associated with the risk of tuberculosis (TB) in different populations. However, IL-10
gene polymorphism and susceptibility to TB in Thai is still unknown.
Objective : The purpose of this study was to evaluate whether the common IL-10 promoter gene polymorphisms are associated
with TB in Thai population.
Material and Method: Forty-eight patients with newly diagnosed pulmonary tuberculosis were studied. DNA samples were
extracted from leukocytes and used to investigate -1087A/G, -819C/T, -252C/A (rs1800896, rs1800871, rs1800872) in IL-10
gene using restriction fragment length polymorphism (PCR-RFLP) methods.
Results : In this study, the genotype and allele frequencies of IL-10-1087A/G, -819C/T, -252C/A polymorphism did not
significantly different between TB patients and healthy controls ((genotype: p = 0.38, p = 0.92, p = 1; allele: p = 0.57, p = 0.77,
p = 0.89, respectively).
Conclusion : The lack of association between common IL-10 promoter polymorphisms and TB susceptibility in this study may
provide clue for better understanding of IL-10-1087A/G, -819C/T, -252C/A polymorphism and TB susceptibility in Thai
population, which might facilitate the rationale design of vaccines. However, further studies in large scales population are
required for confirmation.
Keywords : IL-10, Cytokines, Single nucleotide polymorphism (SNP), Tuberculosis
