Trinucleotide repeat sequence-based PCR as a potential approach for genotyping Mycobacterium gordonae strains

Area of Science:

• Microbiology
• Genetics
• Epidemiology

Background:

• Non-tuberculous mycobacteria (NTM) cause challenging diseases with significant epidemiological importance.
• Current genotyping methods for Mycobacterium gordonae are inadequate for precise strain tracking.
• Accurate genotyping is crucial for understanding NTM disease transmission and control.

Purpose of the Study:

• To develop and evaluate a rapid, reproducible genetic assay for Mycobacterium gordonae genotyping.
• To establish a single-primer PCR screening method for M. gordonae.
• To compare the efficacy of the novel assay with existing Enterobacterial Repetitive Intergenic Consensus Sequences (ERIC)-PCR.

Main Methods:

• Development of a trinucleotide repeat sequence-based PCR (TRS-PCR) assay using M. gordonae strains.
• Application of 10 different TRS-containing primers, focusing on a (CAC)₄-based primer.
• Genotyping of 36 M. gordonae strains and comparison with ERIC-PCR results.

Main Results:

• The (CAC)₄-based TRS-PCR achieved a high discriminatory index of 0.975 and 92% reproducibility.
• The novel TRS-PCR method demonstrated superior performance compared to ERIC-PCR (0.93 discriminatory index, 86.3% reproducibility).
• The proposed method is a useful single-primer PCR screen for M. gordonae.

Conclusions:

• Trinucleotide repeat sequence-based PCR (TRS-PCR) provides a highly effective and reproducible genotyping method for Mycobacterium gordonae.
• This novel assay offers significant advantages over existing methods like ERIC-PCR for epidemiological studies of NTM.
• The developed TRS-PCR assay facilitates better strain differentiation and tracking of M. gordonae infections.