16S rRNA Amplicon Sequencing
Definition
A targeted sequencing approach that amplifies a variable region of the bacterial 16S ribosomal RNA gene, which acts as a universal phylogenetic marker. It is cheaper and simpler than shotgun metagenomics and is the dominant method in current forensic microbiome research.
- Target
- Variable region of the bacterial 16S rRNA gene
- Cost/complexity
- Cheaper and simpler than shotgun metagenomics
- Status
- Dominant method in forensic microbiome research
Common questions
Why not use shotgun metagenomics by default instead?+
Shotgun sequencing needs more input DNA, generates far more data to process and costs more per sample, while amplicon sequencing with universal 16S primers gives adequate taxonomic resolution for most forensic microbiome questions at a fraction of the effort.
What is a known drawback of amplicon sequencing compared to shotgun methods?+
PCR primer bias can under- or over-represent certain bacterial groups, and because only a marker gene is sequenced, no functional or metabolic information about the microbial community is captured, unlike whole-genome shotgun data.
Related terms
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