Origin and diffusion of mtDNA haplogroup X.
A maximum parsimony tree of 21 complete mitochondrial DNA (mtDNA) sequences belonging to haplogroup X and the survey of the haplogroup-associated polymorphisms in 13,589 mtDNAs from Eurasia and Africa revealed that haplogroup X is subdivided into two major branches, here defined as "X1" and "X2." The first is restricted to the populations of North and East Africa and the Near East, whereas X2 encompasses all X mtDNAs from Europe, western and Central Asia, Siberia, and the great majority of the Near East, as well as some North African samples. Subhaplogroup X1 diversity indicates an early coalescence time, whereas X2 has apparently undergone a more recent population expansion in Eurasia, most likely around or after the last glacial maximum. It is notable that X2 includes the two complete Native American X sequences that constitute the distinctive X2a clade, a clade that lacks close relatives in the entire Old World, including Siberia. The position of X2a in the phylogenetic tree suggests an early split from the other X2 clades, likely at the very beginning of their expansion and spread from the Near East.
Reidla
Maere
M
Department of Evolutionary Biology, Institute of Molecular and Cell Biology, Tartu University and Estonian Biocentre, Tartu, Estonia. mreidla@ebc.ee
Kivisild
Toomas
T
Metspalu
Ene
E
Kaldma
Katrin
K
Tambets
Kristiina
K
Tolk
Helle-Viivi
HV
Parik
Jüri
J
Loogväli
Eva-Liis
EL
Derenko
Miroslava
M
Malyarchuk
Boris
B
Bermisheva
Marina
M
Zhadanov
Sergey
S
Pennarun
Erwan
E
Gubina
Marina
M
Golubenko
Maria
M
Damba
Larisa
L
Fedorova
Sardana
S
Gusar
Vladislava
V
Grechanina
Elena
E
Mikerezi
Ilia
I
Moisan
Jean-Paul
JP
Chaventré
André
A
Khusnutdinova
Elsa
E
Osipova
Ludmila
L
Stepanov
Vadim
V
Voevoda
Mikhail
M
Achilli
Alessandro
A
Rengo
Chiara
C
Rickards
Olga
O
De Stefano
Gian Franco
GF
Papiha
Surinder
S
Beckman
Lars
L
Janicijevic
Branka
B
Rudan
Pavao
P
Anagnou
Nicholas
N
Michalodimitrakis
Emmanuel
E
Koziel
Slawomir
S
Usanga
Esien
E
Geberhiwot
Tarekegn
T
Herrnstadt
Corinna
C
Howell
Neil
N
Torroni
Antonio
A
Villems
Richard
R
D000349:Africa; D001208:Asia; D004272:DNA, Mitochondrial / Q000235:genetics*; D004641:Emigration and Immigration; D005060:Europe; D014644:Genetic Variation / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007198:Indians, North American / Q000235:genetics; D010802:Phylogeny; D011110:Polymorphism, Genetic / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics
D004272:DNA, Mitochondrial