Genotyping of HLA-B27 Sequence Specific Alleles in Ankylosing Spondylitis and Uveitis Patients

Abstract

Background: Proper prognosis in Ankylosing Spondylitis and Uveitis Patients is clinically significant and thus the role of HLA-B27 genotyping is an important parameter to evaluate and follow up the patients. Aims : We characterize the HLA-B27 Sequence Specific Alleles (SSA) in Ankylosing Spondylitis and Uveitis Patients. Settings and Design: Total of 153 cases were considered having symptoms which include stiffness in the lower back and buttocks, tenderness at the heel and 13 cases were with Inflammation of eye (Uveitis or Iritis). Methods and Material: Molecular tools were employed, which included DNA extraction and sequence specific alleles amplification for all the cases to reveal the HLA-B27 SSA genotypic distribution. Results: Out of 153 patients studied, 140 symptomatic for Ankylosing Spondylitis (AS) and 13 for Uveitis, 61(40%) were positive for HLA-B27 PCR out of which 58(41.4%) were positive from AS category and 03(23%) cases for Uvetis. Molecular characterization of the alleles further revealed that in AS positive cases, Group A and Group B alleles got amplified in 55 (39.2%) patients, whereas only 02 (1.4%) and 01(0.7%) cases were with Group A and Group B respectively. In Uvetis, all the 03 positive cases were with both Group A and Group B alleles. Conclusions: The presence of Group A (1.4%) and Group B (0.7%) alleles in the AS patients confirming it to be a necessary tool for AS screening. Present study suggest to use HLA-B27 PCR for the diagnosis of AS, Reiters Syndrome, Uveitis, Iritis, and inflammatory bowel disease at molecular level but must be done and considered with both the sequence specific alleles to avoid false results.