Although several genetic loci have been associated with susceptibility to developing leprosy, a group conducted a large-scale study based on a case-control study with leprosy using a gene-centric 50-K microarray, covering variants in 2,092 genes throughout the genome (Keating et al., 2008) and found the TLR1 and HLA-DRB1/DQA1 genes as main determinants of leprosy susceptibility. The gene discussed is TLR1; the disease is leprosy.