CCDC122 (coiled-coil domain containing 122) is a genetic locus associated with susceptibility to leprosy across multiple populations. The gene was identified through genome-wide association studies as significantly linked to Mycobacterium leprae infection risk 1. Specific polymorphisms in CCDC122, particularly rs4942254, show protective effects against leprosy development, with the CC genotype conferring reduced disease risk in Brazilian and Chinese populations 23. CCDC122 functions within the NOD2-mediated innate immune signaling pathway 1, and its expression is significantly upregulated in leprosy-affected tissues compared to normal skin 4. The gene's role extends beyond leprosy susceptibility; recent evidence indicates CCDC122 undergoes alternative splicing regulation associated with schizophrenia risk, with splicing quantitative trait loci affecting its expression in brain tissues, particularly in oligodendrocytes and microglia 5. The consistent association of CCDC122 variants with leprosy across diverse ethnicities—including Chinese Han, Chinese Yi, Brazilian, Vietnamese, and Amazonian populations—indicates robust genetic effects 67. These findings implicate CCDC122 in regulating innate immune responses critical for controlling mycobacterial infections and potentially neuroinflammatory processes.