rCRS (Revised Cambridge Reference Sequence)
Definition
The standard reference sequence for the human mitochondrial genome (NC_012920.1, 16,569 bp), used as the coordinate system for reporting all forensic mtDNA results. Sequenced by Sanger method (Andrews et al., 1999); differences between a sample and the rCRS are reported as substitutions, insertions, or deletions at numbered positions.
- Accession number
- NC_012920.1
- Length
- 16,569 base pairs
- Method used
- Sanger sequencing
- Publication
- Andrews et al., 1999
Common questions
Why does forensic mtDNA reporting need a fixed reference sequence at all?+
Mitochondrial genomes vary between people, so a report needs one common numbering scheme to describe a sample's variants as positions and changes relative to it, letting laboratories compare results consistently across cases and databases.
Does everyone match the rCRS exactly at the mitochondrial positions that matter?+
No. Most people carry several differences from the rCRS scattered through their mitochondrial genome; these differences, not identity with the reference, are what a forensic mtDNA comparison actually evaluates.
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