Comparison of different methods for the detection of HLA-B* 57:01 allele in people living with HIV in Eastern Uttar Pradesh, India.

BACKGROUND: The gold standard for detecting HLA-B*57:01 allele linked to Abacavir hypersensitivity is sequence-based typing (SBT), which is labour-intensive, not readily available and needs special expertise. HCP5 gene polymorphism is a surrogate marker for HLA-B*57:01 allele. Therefore, we compared, nested PCR for HLA-B*57:01 allele, HCP5 PCR with SBT method to develop a simple and cost-effective method for detection of HLA-B*57:01 allele. METHOD: Whole blood cells were collected from PLHIV and Buffy coat and DNA was isolated. Direct PCR for HLA-B*57 gene followed by nested PCR for the HLA-B* 57:01 allele and HCP5 gene PCR was done in all patients. The PCR results of both methods were confirmed by the SBT method. RESULT: Among 366 samples, 25 (6.83%) were positive for HLA-B* 57:01 allele by nested PCR. HCP5 gene PCR was positive in 25 (6.83%) individuals who were also positive for the HLA-B*57:01 allele with nested PCR. A strong correlation was observed between the HLA-B*57:01 allele and HCP5 with negative and positive predictive values of 100% respectively in our population. CONCLUSION: Nested (two-step) and HCP5 gene PCR (single-step) are simple, rapid and cost-effective methods for HLA-B*57:01 allele detection and either can be adapted in the ART centre located in resource-poor settings.