title: Associations of HLA-DRB1, DQB1 and DPB1 alleles with pulmonary tuberculosis in south India.
abstract: METHODS
  Tuberculosis is endemic in south India: sputum positive pulmonary tuberculosis is predisposed by HLA-DR2 in south India and few other populations of the world.
  
  
  OBJECTIVE
  To study HLA-DRB1, DQB1, DQA1 and DPB1 allelic polymorphism in pulmonary tuberculosis patients and endemic controls from south India.
  
  
  METHODS
  One hundred and twenty-six, sputum positive pulmonary tuberculosis patients and 87, endemic controls, from Madurai were studied for MHC class II allelic polymorphism by PCR-SSOP method. XI IHWC primers and probes and non-radioactive probing methods were employed.
  
  
  RESULTS
  HLA DRB1*1501 and DQB1*0601 predisposed for pulmonary tuberculosis (DRB1*1501: odds ratio (OR) = 2.68, 95% confidence interval (CI) = 1.30-5.89, P value (P) = 0.013, aetiological fraction (EF) = 0.17; DQB1*0601: OR = 2.32, CI = 1.29-4.27, P = 0.008, EF = 0.26). Haplotype DRB1*1501-DQB1*0601 was higher in patients (1324 per 10,000, X2 = 27.07) than controls (F = 404/10,000, X2 = 8.84). In a subset of 63 caste matched samples, DPB1*04 was preventive (OR = 0.45, CI = 0.21-0.95, P = 0.036, PF = 0.26): the distributions of DRB1*1501-DQB1*0601-DPB1*04 phenotypes were different between patients and controls (P = 0.0092). These alleles were predominant in patients and controls of T5SU caste.
  
  
  CONCLUSIONS
  HLA-DRB1*1501 and DQB1*0601 predisposed to sputum positive pulmonary tuberculosis, and DPB1*04 was preventive and epistatic to this risk. Caste T5SU is an ideal model to study immunology of tuberculosis.
authors.affiliation: Department of Immunology, School of Biological Sciences, Madurai Kamaraj University, India.
authors.forename: M
authors.initials: M
authors.lastname: Ravikumar
authors.forename: V
authors.initials: V
authors.lastname: Dheenadhayalan
authors.forename: K
authors.initials: K
authors.lastname: Rajaram
authors.forename: S S
authors.initials: SS
authors.lastname: Lakshmi
authors.forename: P P
authors.initials: PP
authors.lastname: Kumaran
authors.forename: C N
authors.initials: CN
authors.lastname: Paramasivan
authors.forename: K
authors.initials: K
authors.lastname: Balakrishnan
authors.forename: R M
authors.initials: RM
authors.lastname: Pitchappan
mesh_terms: D000328:Adult; D000483:Alleles; D020022:Genetic Predisposition to Disease; D006681:HLA-D Antigens / Q000235:genetics*; D006682:HLA-DP Antigens / Q000235:genetics; D059868:HLA-DP beta-Chains; D006683:HLA-DQ Antigens / Q000235:genetics; D059866:HLA-DQ beta-Chains; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006239:Haplotypes; D006650:Histocompatibility Testing; D006801:Humans; D007194:India; D010641:Phenotype; D016133:Polymerase Chain Reaction; D014397:Tuberculosis, Pulmonary / Q000235:genetics*
chemical_list: D006681:HLA-D Antigens; D006682:HLA-DP Antigens; D059868:HLA-DP beta-Chains; C071170:HLA-DPB1 antigen; D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains