Fig. 1.

Molecular identification of Histoplasma capsulatum by conventional PCR. A. Successful amplification with specific primer sets and Histoplasma capsulatum isolate CEMM 05-2-035 (=H2) as a template. Lane 1, 100 bp DNA ladder (Fermentas, USA) for size determinations; Lane 2, Msp2F-Msp2R primer pair amplification (279 bp); Lane 3, 1281-1283₂₂₀ primer pair amplification (PCR 220; 220 bp); Lane 4, 1281-1283₂₃₀ primer pair amplification (PCR 230; 230 bp); Lane 5, negative control. Further information about isolates used and amplification success can be found in Table S1. B. Receiver operating characteristic (ROC) curves for primer pairs Msp2F-Msp2R (MSP2), 1281-1283₂₂₀ (PCR 220) and 1281-1283₂₃₀ (PCR 230) based on 104 specimens. Despite high genetic diversity across H. capsulatum clusters, primer pairs usually employed in diagnosis successfully identified the new genetic groups recognised in this study. In PCR220 and PCR230, lines are superimposed, indicating equivalent accuracy. The classification variable was a dichotomous variable that indicated the diagnosis (0 = negative, 1 = positive).