Biogeographic Ancestry Inference (BGA)
Definition
Statistical assignment of a donor to continental ancestry groups using Ancestry-Informative SNPs (AIMs). Distinct from racial categorisation.
- Method
- Statistical continental ancestry assignment
- Markers used
- Ancestry-Informative SNPs (AIMs)
- Output
- Probabilistic group assignment
- Distinction
- Not equivalent to racial categorisation
Common questions
How does BGA differ from a standard STR-based DNA profile?+
A standard STR profile is used for individual identification and matching, while BGA uses a different marker set, AIMs, to statistically estimate the likely continental ancestry of an unknown DNA donor, typically to help narrow an investigative lead.
Why is BGA output described as probabilistic rather than definitive?+
The underlying SNP markers show statistical frequency differences between continental populations rather than being unique to one group, so results are reported as likelihoods or percentage admixture estimates, not a certain categorical answer.
Related terms
- Body-Fluid-Specific Transcripts
- RNA markers expressed only in one fluid: HBB for blood, STATH for saliva, PRM1 for semen, MUC4 for vaginal fluid, MMP7 for...
- Deconvolution
- A computational technique that estimates the PSF and inverts its effect to recover a sharper image. The quality depends entirely on how...
- Externally Visible Characteristics (EVCs)
- Traits a witness could see: eye, hair, skin colour, freckling, hair shape, height. The EU-funded VISAGE consortium targets this set.
- Forensic DNA Phenotyping (FDP)
- Prediction of externally visible characteristics, ancestry and age of an unknown donor from SNP genotypes. Investigative lead, not identification.
- HIrisPlex-S
- A 41-SNP externally visible characteristics (EVC) panel for simultaneous prediction of eye, hair, and skin colour, developed at Erasmus MC Rotterdam by...
- mRNA / miRNA
- Messenger and micro RNA. Forensic RNA profiling uses tissue-specific transcripts of both classes to identify body fluids.
- Parabon Snapshot
- A commercial DNA phenotyping service (Parabon NanoLabs, Virginia, US) that genotypes thousands of SNPs from a crime-scene sample and uses machine learning...
- SNP
- Single Nucleotide Polymorphism. A one-base variant at a defined position. FDP uses SNP panels, not STRs.