STRUCTURE / ADMIXTURE
Definition
Software tools that infer population structure by estimating each individual's fractional ancestry (membership coefficient) across K genetic clusters. Used to assign unknown samples to source populations and to visualise admixture between groups.
- Software examples
- STRUCTURE, ADMIXTURE
- Output
- Ancestry membership coefficients
- Key parameter
- K, number of genetic clusters
- Use
- Assigns samples to source populations
Common questions
How do STRUCTURE and ADMIXTURE differ in approach?+
STRUCTURE uses a Bayesian Markov chain Monte Carlo method to estimate ancestry proportions, while ADMIXTURE uses a faster maximum-likelihood algorithm designed to scale to much larger genomic datasets, generally producing comparable results with less computing time.
How is the number of clusters, K, chosen for an analysis?+
Analysts typically run the software across a range of K values and use a statistical criterion, such as the rate of change in likelihood between successive K values, to identify the K that best explains the structure present in the data.
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