Association between MBL2 gene polymorphism and protection against leprosy in a population of northeastern brazil: a case-control study.

Leprosy is a chronic and neglected infectious disease caused by the bacilli Mycobacterium leprae and Mycobacterium lepromatosis, and is considered a public health problem. The genetic basis of the host is a determining factor in the development of the disease, highlighting genetic mutations in the MBL2 gene. The aim of this study was to investigate the associations of the rs1800450 polymorphism in the MBL2 gene in populations from Northeastern Brazil. A retrospective case-control genetic association study was conducted in the state of Alagoas, with replication in a population from Pernambuco/Bahia. The case group included patients diagnosed with leprosy, whereas the control group included healthy individuals. The participants' DNA was extracted via the salting-out method and genotyped via real-time PCR. The allele and genotypic frequencies of the MBL2 (rs1800450) were obtained and subsequently compared between groups via logistic regression. In the population of Alagoas, 556 individuals were recruited, of which 292 were cases and 264 were healthy controls. A statistically significant association was observed between the SNP rs1800450 at MBL2 gene and protection against leprosy, for both the CT genotype (OR = 0.49, p = 0.001, CI = 0.32-0.75), for the T allele and for T carriers (p = 0.046, OR = 0.51, CI = 0.34-0.78; p = 0.002, OR = 0.51, CI = 0.34-0.78, respectively). However, no association was observed in the replication population. When combining the populations, it continued to show a significant association with protection against leprosy in the CT genotype (p = 0.004, OR = 0.66, CI = 0.51-0.87) and in T carriers (p = 0.009, OR = 0.70, CI = 0.54-0.91) even when adjusted by sex. The SNP rs1800450 in the MBL2 gene was associated with leprosy protection in a population from Northeastern Brazil.