HLA-DRB1, DQB1 allele frequencies in Iranian patients (sistani ethnic) with tuberculosis and healthy control

HLA disease association was investigated in several autoimmune, cancer and infectious diseases. The outcome of tuberculosis (TB) infection may be influenced by host genetic factors like MMP-1, MCP-1, IL-10, IL-12, TNF-α, IFN-γ and human leukocyte antigen (HLA). Given the paucity of information with regard to the association between the human leukocyte antigens (HLA) and TB infection among Iranians, we aimed to identify HLA polymorphisms that might confer susceptibility or protect against TB.
In this case-control study, to investigate the association between the HLA-DRB1 and DQB1 alleles and TB, 50 patients with tuberculosis were selected from Sistani population in Golstan University of Medical Sciences, Golestan Province, North East of Iran, from September 2015 to February 2016. Allele frequencies in patients were compared with a 100 aged and sex match control group from healthy blood donor of that ethnic population. HLA-DRB1 and -DQB1 alleles were determined using polymerase chain reaction based on sequence specific primer (PCR-SSP) method by low to intermediate resolution kits supplied by CTS (Collaborative Transplant Study, Heidelber University, Germany). Using EPI-info statistical software Chi-square test and fisher exact test, 95% confidence interval and odd ratio were calculated and allele frequencies in patients and control subjects were compared. P-value less than 0.05 were considering statistically significant.
The results of this study showed a significant increase and positive association with -DRB1*04:03 (OR=3.13, CI 95% (2.47-3.96), -DRB1*14:04 (OR=3.13, CI 95% (2.47-3.96), -DQB1*0201 (OR=2.67, CI 95% (1.18-6.04), -DQB1*0601 (OR=3.16, CI 95% (1.36-7.73) ,while the frequency of -DRB1*07 (OR=0.16, CI 95% (0.05-0.52) were lower in patients than control group and shows negative association.
The results of this study confirmed some of the previous positive and/or negative association, however it is suggested that HLA-DRB1*04:03, -DRB1*14:04, -DQB1*0201, -DQB1*0601- have an important role in susceptibility to tuberculosis infection and -DRB1*07 was associated with protection in Iranian Sistani population. Larger case-control sample size studies may be helpful to confirm our investigation. In addition population-specific studies is needed for evaluation of the role of HLA polymorphisms in tuberculosis in different ethnic groups.