title: A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar.
abstract: BACKGROUND
  Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model.
  
  
  RESULTS
  Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central highlanders (n = 266). Complete mitochondrial DNA genome sequences reveal several unresolved lineages, and a new, deep branch of the out-of-Africa founder clade M has been identified. This new haplogroup, M23, has a limited global distribution, and is restricted to Madagascar and a limited range of African and Southwest Asian groups.
  
  
  CONCLUSIONS
  The geographic distribution, phylogenetic placement and molecular age of M23 suggest that the colonization of Madagascar was more complex than previously thought.
authors.affiliation: CNRS FRE 2960, Laboratoire d'Anthropobiologie, Université de Toulouse, Toulouse III Paul sabatier, 31073 Toulouse cedex 3, France. fx.ricaut@infonie.fr
authors.forename: François-X
authors.initials: FX
authors.lastname: Ricaut
authors.forename: Harilanto
authors.initials: H
authors.lastname: Razafindrazaka
authors.forename: Murray P
authors.initials: MP
authors.lastname: Cox
authors.forename: Jean-M
authors.initials: JM
authors.lastname: Dugoujon
authors.forename: Evelyne
authors.initials: E
authors.lastname: Guitard
authors.forename: Clement
authors.initials: C
authors.lastname: Sambo
authors.forename: Maru
authors.initials: M
authors.lastname: Mormina
authors.forename: Marta
authors.initials: M
authors.lastname: Mirazon-Lahr
authors.forename: Bertrand
authors.initials: B
authors.lastname: Ludes
authors.forename: Eric
authors.initials: E
authors.lastname: Crubézy
mesh_terms: D044383:Black People / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D030561:Databases, Nucleic Acid; D019143:Evolution, Molecular; D005828:Genetics, Population; D015894:Genome, Human; D054629:Genome, Mitochondrial; D006239:Haplotypes; D006801:Humans; D008270:Madagascar; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial