Abstract
BACKGROUND: Autoimmune hepatitis is a polygenic disorder of unknown etiology, where genetic factors affect the occurrence and clinical phenotype of the disease. It has been reported as a rare disease entity in the Indian subcontinent. This study was undertaken to investigate the association of HLA alleles with autoimmune hepatitis type 1 and type 2 in north Indian population and to analyze if distinct human leukocyte antigen (HLA) alleles help in characterization of the subtypes of autoimmune hepatitis. METHODS: Sixty-eight patients with autoimmune hepatitis and 128 healthy controls were recruited in the study. Out of 68 patients, 55 were diagnosed with autoimmune hepatitis type 1 and 13 with autoimmune hepatitis type 2. The patients and the controls were typed for HLA class II alleles by PCR-SSP method. RESULTS: HLA DRB1*04 and DRB1*08 were found to be significantly associated with autoimmune hepatitis type 1 in north Indian population. It was also observed that DRB1*04, DRB1*13 were significantly associated with pediatric autoimmune hepatitis type 1 and DRB1*08 was significantly associated with adult autoimmune hepatitis type 1. DRB1*14 was significantly associated with autoimmune hepatitis type 2. CONCLUSION: The study indicates that autoimmune hepatitis in north Indian population is associated with HLA alleles that may help to discriminate the subtypes as autoimmune hepatitis type 1 and type 2. The study also highlights the ethnic variations in the Indian subcontinent in context to the genetic association of HLA with autoimmune diseases.