Background: Celiac disease (CeD) has been strongly linked to different HLA (Human Leukocyte Antigen) genotypes (mainly HLA-DQ2.2, 2.5, and 8) that are known to show susceptibility to celiac disease. Absence of these genotypes may help in ruling out celiac disease. Luminex® technology is a standard fluorescence-based genotyping technique that provides intermediate/high resolution for the complete HLA DQA1/DQB1 gene; however, it requires availability of a Luminex fluorescent detection analyzer. CeliaSCAN method is an easy-to-use multiplex real-time PCR assay with melting curve analysis for detecting HLA genotypes. This study is designed to compare the two methods for their ability to detect these HLA genotypes in CeD patients.
Methods: Blood samples were taken from 248 diagnosed CeD patients based on positive anti-tissue-transglutaminase (tTG) antibody serology and biopsy findings, and 25 controls (non-celiac dyspepsia patients). DNA extracted from whole-blood samples was quantified and assessed for quality. DNA from each patient and control was analysed for HLA typing using two methods: the Luminex LABType SSO Typing Technique and the real-time PCR-based CeliaSCAN technique. The percentage concordance between the two techniques was calculated.
Results: While the Luminex technique detected HLA DQ 2.2/2.5/8 genotypes in 93.4% of patients with CeD, the CeliaSCAN method was able to detect them in 92.3% of patients. In the control group, 78.1% and 81% of controls were detected to have these genotypes by CeliaSCAN and Luminex methods, respectively. Overall, both techniques exhibited 95.3% concordance with each other.
Conclusion: HLA genotyping results by CeliaSCAN were comparable to those from Luminex assays. Though Luminex assays provide high-resolution results, CeliaSCAN proves to be a feasible real-time PCR-based method for analyzing the HLA DQ2.2/2.5/8 genotypes when infrastructure for Luminex assays is not available.