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Updated: Jul 18, 2026
09:03
Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
Published on: September 5, 2013
Staphylococcal chromosome cassette evolution in Staphylococcus aureus inferred from ccr gene complex sequence typing
1INSERM E0230, Université Lyon 1, Centre National de Référence des Staphylocoques, Faculté Laennec, Lyon, France. gerard.lina@chu-lyon.fr
Summary
Methicillin-resistant Staphylococcus aureus (MRSA) SCCmec elements show limited recombination but multiple acquisitions by S. aureus. SCCmecIV ST-SCCmec10 is the most common, potentially originating in a paediatric clone.
Area of Science:
- Microbiology
- Genetics
- Epidemiology
Background:
- Staphylococcal chromosome cassette mec (SCCmec) elements are crucial for methicillin resistance in Staphylococcus aureus (MRSA).
- Understanding SCCmec diversity and evolution is key to tracking MRSA spread and developing control strategies.
Purpose of the Study:
- To characterize SCCmec elements in major healthcare- and community-associated MRSA clones.
- To investigate the evolutionary relationships and acquisition patterns of SCCmec elements.
Main Methods:
- Intra-SCCmec multilocus sequencing was employed to analyze SCCmec elements.
- Phylogenetic analysis of SCCmec loci was performed using concatenated sequences.
- Comparison with PCR-based typing methods was conducted.
Main Results:
- A strong correlation was found between sequence- and PCR-based typing methods (p <0.001).
- Phylogenetic analysis revealed limited recombination events within SCCmec loci.
- Sequence type (ST)-SCCmec1 was identified in both SCCmec types I and IV, suggesting element evolution.
- No correlation between ST-SCCmec lineage and MRSA lineage was observed, indicating multiple SCCmec acquisitions.
- SCCmecIV ST-SCCmec10 was the most frequently acquired element, found across all examined clonal complexes.
Conclusions:
- SCCmec elements exhibit complex evolutionary histories with multiple independent acquisitions by S. aureus.
- The SCCmecIV ST-SCCmec10 element represents a significant factor in MRSA epidemiology, potentially originating in a paediatric clone.
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