Frequency analysis of HLA-B allele in leukemia patients from a North Indian population: A case-control study

Background: HLA-B gene is reported to have the highest number of allelic variants among the other HLA class I genes. It is suggested that the HLA-B gene has a particular ability to affect the activity of some immune responses mainly those related to lymphoproliferative neoplasia triggered by intracellular pathogens. Although, several studies have been conducted to study HLA polymorphism and distribution of HLA alleles in different populations and ethnic groups, the scarcity of comparable findings in India encouraged us to examine the possible HLA-B leukemia association in the North Indian population. Objective: To determine the allelic frequencies of HLA-B and their association with leukemia in a North Indian population. Material and methods: A total of 583 patients (case) diagnosed with leukemia as well as 1188 healthy individuals (control) were studied for a period of 4 years (February 2015-March 2019). All these samples (cases and controls) were typed for HLA-B allele by polymerase chain reaction- sequence-specific oligonucleotide probe (PCRS-SOP) method based on Luminex platform. Results: We found an increased frequency of HLA-B*07:02 (5.75% versus 4.42%) in cases as compared to the control group. Similarly, frequency of HLA-B*15:01 (2.3% versus 1.38%), B*15:25 (0.43% versus 0.08%), B*18:01 (3.60% versus 2.81%) and B*44:03 (8.75% versus 6.01%) were found to be increased in cases as compared to the controls. These results suggest that HLA-B*15:25 (p = 0.048, OR = 4.49, 95% CI), 38:02 (p = 0.002, OR = 3.97, 95% CI), 44:03 (p = 0.003, OR = 1.48, 95% CI) have a positive association whereas HLA-B*08:01 (p <= 0.001, OR = 0.48, 95% CI) has a negative association with leukemia. Conclusions: Our results provide the first evidence of the HLA-B allele association with leukemia in the North Indian population. Further, it is suggested that HLA-B*15:25, B*38:02, and HLA-B*44:03 alleles may play a presumptive predisposing factor while the HLA-B*08: 01 allele could be a protective genetic factor against leukemia in the North Indian population.