HLA- DR Alleles in Pakistani Patients of Pemphigus Vulgaris

ABSTRACT

Objective: To determine frequency of HLA-DR alleles in Pakistani patients of pemphigus vulgaris in comparison with local healthy controls. Study Design: Cross-sectional, comparative study. Place and Duration of Study Department of Immunology, Armed Forces Institute of Pathology [AFIP], Rawalpindi, from January 2011 to January 2014. Methodology: Twenty eight patients with biopsy proven diagnosis of pemphigus vulgaris referred from Department of Dermatology, Military Hospital, Rawalpindi were included. Patients were compared with a group of 150 unrelated local healthy subjects. DNA was extracted from peripheral blood collected in Tri-potassium EDTA. HLA-DRB1 typing was carried out on allele level [DRB1*01 - DRB1*16] using SSP [sequence specific primers]. HLA type was determined by agarose gel electrophoresis and results recorded. Phenotype frequency of various alleles among patient group and control group was calculated by direct counting and significance of their association was determined by Fisher's exact test/ Chi square test. Results: A total of 12 male and 16 female patients, with age ranging from 21 to 34 [mean 23.4 years] were genotyped for HLA-DRB1 loci. A statistically significant association of the disease with HLA-DRB1*04 was observed [50% versus 20.7% in controls, p < 0.05]. Conclusion: There is a strong association of HLA-DRB1*04 with pemphigus vulgaris in Pakistani population. Key Words Pemphigus vulgaris. Human leukocyte antigen. Pakistan. Haplotype.