mtDNA, fair game or folly?

RPM and Kambiz comment on a paper which argues for the utility of mtDNA in phylogeography.

Remember,

  • there is lots of mtDNA that is easy to extract because there are so many mitochondria within eukaryotic cells
  • it mutates fast, building up a lot of genetic variation, in a neutral matter (i.e., perfect "clock")
  • it is uniparental, passed from mother to daughter, making the coalescent model congenially tractable
Tags

More like this

Dienekes points me to a new paper, Demographic history of Canary Islands male gene-pool: replacement of native lineages by European (PDF). Here are the results: Autochthonous (E-M81) and prominent (E-M78 and J-M267) Berber Y-chromosome lineages were detected in the indigenous remains, confirming a…
When Mendelism reemerged in the early 20th century to become what we term genetics no doubt the early practitioners of the nascent field would have been surprised to see where it went. The centrality of of DNA as the substrate which encodes genetic information in the 1950s opened up molecular…
Evolgen has a nice little post up on the problems with mitochondrial DNA (mtDNA) in regards to using it to infer demographic history. This form of genomic information is useful in that it is relatively copious, being present in the hundreds of mitochondrion to be found within every cell. This is…
A neat new paper on Icelandic genetics, then and now, Sequences From First Settlers Reveal Rapid Evolution in Icelandic mtDNA Pool: A major task in human genetics is to understand the nature of the evolutionary processes that have shaped the gene pools of contemporary populations. Ancient DNA…

It's not so much the phylogentic utility of mtDNA that's in question, it's whether mtDNA polymorphism adequately captures population size changes.

it mutates fast, building up a lot of genetic variation, in a neutral matter

But that's what's being called into question! Any selection at any site in the molecule will affect polymorphism everywhere else on the molecule.

It's not that mtDNA is a poor locus for popgen analysis. mtDNA is like any other locus. We need to sample multiple independent loci to understand demographic history.