All of the VNTRs were efficiently amplified in each M. hominis isolate tested. The size variation of the amplicons
was exact multiples of the repeats (Table 2). This was confirmed by sequencing amplicons which presented an unexpected size variation using the capillary electrophoresis analysis. The marker Mho-53 was the most discriminatory VNTR, displaying six different allele sizes with repeat copy numbers ranging from 3 to 8, depending on the isolate. The markers Mho-50 and Mho-52 showed five and three different allele sizes, respectively. The other markers yielded only two different-sized PCR products. The marker Mho-116 was the most homogenous marker, as almost all of the isolates harboured one repeat (three harboured two copies). This finding Selleck GSK2879552 was reflected by the diversity index of each VNTR, estimated high throughput screening from the HGDI, with a value of 0.784 for the most discriminatory marker (Mho-53) and a value of 0.020 for the less discriminatory one (Mho-116). The overall discriminatory index of the MLVA assay was 0.924. Table 2 Number of repeat units for the five VNTR markers MLVA type No. of repeats at the following VNTR loci
Mho-50 Mho-52 Mho-53 Mho-114 Mho-116 1 1 8 8 1 1 2 1 8 3 1 1 3 1 8 3 2 1 4 1 8 4 1 1 5 1 8 4 2 1 6 1 8 4 2 2 7 1 8 5 1 1 8 1 8 5 2 1 9 1 8 6 1 1 10 1 8 6 2 1 11 1 8 7 1 1 12 1 8 7 2 1 13 1 8 8 2 1 14 3 8 3 1 1 15 1 9 3 2 1 16 1 9 4 1 1 17 1 9 4 2 1 18 1 9 5 2 1 19 2 8 3 1 1 20 2 8 3 2 1 21 2 8 4 1 1 22 2 8 4 2 1 23 2 8 5 2 1 24 2 9 7 1 1 25 3 8 3 2 1 26 3 8 4 1 1 27 3 8 4 2 1 28 3 8 5 2 1 29 3 8 6 2 1 30 3 8 7 2 1 31 3 9 4 2 1 32 3 9 7 2 1 33 4 8 3 2 2 34 4 8 4 2 1 35 4 8 5 2 1 36 4 8 6 2 1 37 5 8 4 2 1 38 1 10 3 2 1 39 1 10 4 2 1 40 1 10 5 2 1 A combined analysis of
the five VNTR loci in the 210 M. hominis isolates revealed 40 MLVA types (Table 2). Three MLVA types, 5, 8 and 10, were present in more than 20 isolates. In 18 cases, one unique MLVA type was observed in a single patient. Interestingly, the two ATCC strains, H34 and M132, had the identical MLVA type 10, while the PG21 ATCC strain belonged to the MLVA type 36. The 167 urogenital isolates were classified into 34 MLVA types (Additional file 1: Quinapyramine Table S1). The 34 extragenital isolates contained 14 MLVA types, including eight MLVA types that had already been described for urogenital isolates.