"MLVA_5: A reduced marker scheme for phylogeographic analysis of Brucella canis".

Canine brucellosis, caused by Brucella canis, is a globally significant zoonosis. This study characterized the genetic diversity of B. canis in Argentina and South America using the MLVA_16 scheme, comparing 110 Latin American strains with 84 Asian strains (from Korea and China). The analysis revealed high overall diversity (Hunter-Gaston Index: 0.97) and marked geographical structuring. Using LASSO logistic regression, we identified a minimal panel of five markers (MLVA-5: BRUCE19, BRUCE18, BRUCE11, BRUCE07, BRUCE16) that optimally preserves the phylogeographic signal on a global scale. This optimized scheme, unlike hypervariable markers, proves robust and efficient for conducting traceability studies and determining the geographical origin of B. canis strains, thus offering an ideal balance between discriminatory power and evolutionary resolution.