Diversity of Mycoplasma hominis clinical isolates from Bordeaux, France, as assessed by multiple-locus variable-number tandem repeat analysis

Abstract

BackgroundMycoplasma hominis is an opportunistic human mycoplasma species that can cause various urogenital infections and, less frequently, extragenital infections. The objective of this work was to study the genetic diversity of this species using a molecular typing method based on multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA).ResultsThe genome content of M. hominis PG21 was analysed for tandem repeats (TRs), and five of the 130 TRs identified were selected for use in an MLVA assay. The method was based on GeneScan analysis of VNTR loci using multiplex PCR with fluorescent dyes and resolution by capillary electrophoresis. This approach was used on a collection of 210 urogenital and extragenital French clinical isolates collected between 1987 and 2009. Forty MLVA types were found. The discriminatory index of our MLVA scheme was 0.924. Using this new typing tool, persistent infection was suggested for six patients and new infection for one patient. Furthermore, mother-to-child transmission was confirmed in the two cases studied. Application of MLVA to a wide range of M. hominis isolates revealed high genotypic diversity and no obvious link between the MLVA type and the isolate year of collection, the patient’s age or sex, the anatomical origin of the isolates or resistance to antibiotics was found.ConclusionsOur MLVA scheme highlights the high genetic heterogeneity of the M. hominis species. It seems too discriminatory to be used for large epidemiological studies but has proven its usefulness for molecular studies at the individual level.

Genomic determination of minimum multi-locus sequence typing schemas to represent the genomic phylogeny of Mycoplasma hominis

“…Furthermore, identical MLST profiles can be used to identify sexual transmission of M. hominis infections or horizontal transmission between mother and baby and may also be used in cases of post-transplant infection. Other methods including MLVA typing of M. hominis isolates from two mother-neonate pairs resulted in the identification of identical MLVA types in each case studied, confirming mother-to-child transmission [9]. This study describes MLST schemes with a DI of 0.97 ST per M. hominis strain, revealing a genetic heterogeneity among this species.…”

“…Multiple locus variable-number tandem-repeat (VNTR) analysis (MLVA) has successfully been used to subtype other mycoplasma species. However, the high genetic heterogeneity of M. hominis restricted the test’s use to individual studies, and was too discriminatory for large epidemic studies [9]. …”

When present, repeats are abundant in respiratory system pathogens besides virulence associated coding DNA sequences of Mycoplasmas

“…Earlier studies have reported trinucleotide motif GAA(n) in pMGA of M. gallisepticum 17,50,51 The most abundant repeat motif is AAT followed by TAA but CG rich trinucleotide repeats are present in few Mycoplasmas (data not shown). Earlier study reports GAT repeats in rpoD gene, ATT repeat in pgsA gene, GAA in oppA gene of M. hominis 53 54 . The present study shows TTC repeats in two hypothetical protein CDS (data not shown) and one in Transport (permease) CDS (data not shown).…”

Capillary electrophoresis based on nucleic acid detection for diagnosing human infectious disease

“…To study their genetic diversities, Férandon et al [125] applied MLVA-CE to analyze 210 urogenital and extragenital clinical isolates. Forty MLVA types were found, and a large scale study of M. hominis isolates analyzed using MLVA revealed high genotypic diversity.…”

“…These results demonstrate that MLVA-CE is effective for genotyping M. hominis. However, this approach is too discriminating to be applied in a large epidemiological study, although it is useful for molecularly studying individual species [125,126].…”