Multi-Locus Sequence Typing (MLST)
Definition
Species-level and strain-level characterisation using DNA sequences from five to seven conserved housekeeping genes. Provides higher resolution than 16S rRNA alone and lower cost than whole-genome sequencing; used as an intermediate step in microbial forensic workflows.
- Genes analysed
- 5 to 7 conserved housekeeping genes
- Resolution
- Higher than 16S rRNA sequencing alone
- Cost
- Lower than whole-genome sequencing
- Role
- Intermediate step in microbial forensic attribution
Common questions
When would an investigator choose MLST over whole-genome sequencing?+
MLST is chosen when strain-level discrimination is needed faster or more cheaply than full genome sequencing allows, such as an early screening step before committing resources to whole-genome comparison of a shortlist of isolates.
What can MLST not resolve that whole-genome sequencing can?+
Because it examines only a handful of conserved genes, MLST can miss fine-scale variation between very closely related strains that whole-genome sequencing, which compares the entire genome, is able to distinguish.
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