Gene conversion is a key driver of diversity hotspots in M. tuberculosis antigens and virulence-associated loci

Gene conversion drives over 300 diversity hotspots in M. tuberculosis, especially within virulence and antigen-related gene families, increasing genetic variation by more than tenfold.

• Why it matters: Understanding the mechanisms behind genetic diversity in M. tuberculosis is crucial for vaccine development and disease control, as these hotspots influence antigenic variation and immune evasion.
• What they did: Using long-read sequencing of 151 global isolates, the study identified recurrent gene conversion events, clustered mutations, and high-diversity regions mainly within PE, PPE, and ESX gene families.
• The result: Findings reveal that gene conversion actively shapes antigenic and virulence diversity, notably in vaccine candidate PPE18, which shows mutations that could alter immune recognition and HLA-II binding.