Comparative study of the genetic diversity of Mycobacterium tuberculosis Complex by Simplified Amplified Fragment Length Polymorphism and Mycobacterial Interspersed Repetitive Unit Variable Number Tandem Repeat Analysis

Abstract

Species within the Mycobacterium tuberculosis (MTB) Complex are genetically monomorphic, hence the need of genotyping methods for a comprehensive understanding of the epidemiology of the disease. The genetic diversity of a Spain collection of eighty-three, GenoType MTBC® -confirmed Mycobacterium tuberculosis clinical isolates was assessed by simplified AFLP and 15-loci MIRU-VNTR. AFLP results showed 7 patterns (P1-P7), Dice´s coefficient was 71% for P1 vs P7 and 96% for P1 vs P2 and P2 vs P4. MIRU-VNTR showed 25 unique patterns and 14 clusters. Lineages found were as follows: Haarlem (23, 36.51%), Cammeroon (2, 3.17%), LAM (12, 19.05%), West African (6, 9.52%) and EAI (1, 1.59%). Discrimination indexes were 0.61 for AFLP and 0.92 for MIRU-VNTR. In conclusion,  MIRU-VNTR is robust and reproducible for MTB genotyping. Simplified AFLP is a relatively easy-to-perform approach that might be useful for screening of isolates or in low resource settings.