Chloroplast Microsatellite (cpSSR)
Definition
A short tandem repeat locus in the chloroplast genome. Maternally inherited and non-recombining in most trees, cpSSR haplotypes diverge geographically and are used for population-of-origin assignment.
- Inheritance
- Maternal, in most tree species
- Recombination
- Non-recombining
- Use
- Geographic population-of-origin assignment
- Applied to
- Timber provenance
Common questions
Why does maternal, non-recombining inheritance make cpSSR useful for timber origin?+
Because chloroplast haplotypes pass unchanged from mother tree to seedling without recombination, geographically distinct populations accumulate distinct haplotype frequencies over generations, letting a cpSSR profile be matched against reference population databases to indicate likely region of growth.
Can cpSSR alone identify an individual tree, the way STR profiling identifies a person?+
No, cpSSR is generally used for population or regional assignment rather than individual identification, since its variability is lower and shared across many related trees. Nuclear microsatellites are used when individual-level or parentage-level resolution is needed.
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