Hyperfunction variant rs708035 of interleukin 1 receptor-associated kinases 2 gene involved in the predisposition of leprosy infection.

Abstract

Mycobacterium leprae (slow-growing bacteria) is the etiological agent for leprosy infection, which is a chronic granulomatous disease. Symptoms initiate with the loss of sensation in the affected areas, which can lead to severe injuries, cuts and burns. IRAK2 (interleukin-1 receptor-associated kinases 2) is reported to function in the regulation of the NFκB pathway. The frequency of the IRAK2 polymorphism (rs708035) was unknown in the Pakistani population. Therefore, the study was designed to identify the role of the rs708035 SNP (single nucleotide polymorphism) in susceptibility to leprosy. The case-control study was designed, and participants were selected by Ridley-Jopling Classification. Blood samples from healthy individuals and patients were collected after ethical approval. Genomic DNA was extracted for the amplification of selected polymorphisms by tetra-primer amplification refractory mutation system polymerase chain reaction. The desired products were observed via agarose gel (2.5%) electrophoresis followed by data analysis using bioinformatics tools (SNP Stats and SHEsis) and statistical tests (odds ratio, OR, and chi square). The study revealed that the mutant genotype (TT) was found to be frequent among cases (22.80%) in comparison with the controls (1.66%). The SNP rs708035 was significantly associated with the progression of leprosy (χ2 = 17.62, p < 0.0001). The targeted SNP significantly increases the risk of leprosy 2.3 times (OR =2.3119, 95% CI1.2729-4.1989, p< 0.01). The genetic model also confirms the significant association of the A/T genotype with leprosy in the over-dominant model (OR =2.83, 95% CI1.16-6.89, p< 0.001). The study revealed a significant association of the targeted SNP with leprosy and provided baseline data regarding the association of rs708035. The current research could be utilized for the preparation of biomarkers by considering a larger sample size. The patients suffering from leprosy faced various comorbidities, including hypertension and diabetes. The study reports for the first time a significant association of interleukin 1 receptor associated kinases 2 (IRAK2) single nucleotide polymorphism (SNP) rs708035 among the Pakistani population (Karachi). The current study provides baseline data to develop diagnostic biomarkers for early detection of leprosy.