Low genetic variation is associated with low mutation rate in the giant duckweed.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30886148.
- Also identified by DOI 10.1038/s41467-019-09235-5 and PMC identifier 6423293.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Mutation rate and effective population size (N<sub>e</sub>) jointly determine intraspecific genetic diversity, but the role of mutation rate is often ignored. Here we investigate genetic diversity, spontaneous mutation rate and N<sub>e</sub> in the giant duckweed (Spirodela polyrhiza). Despite its large census population size, whole-genome sequencing of 68 globally sampled individuals reveals extremely low intraspecific genetic diversity. Assessed under natural conditions, the genome-wide spontaneous mutation rate is at least seven times lower than estimates made for other multicellular eukaryotes, whereas N<sub>e</sub> is large. These results demonstrate that low genetic diversity can be associated with large-N<sub>e</sub> species, where selection can reduce mutation rates to very low levels. This study also highlights that accurate estimates of mutation rate can help to explain seemingly unexpected patterns of genome-wide variation.
Medical subject headings
- Araceae
- Genetic Variation
- Genome, Plant
- Mutation Rate
- Plant Dispersal