|
Analysis of mitochondrial DNA diversity
in the aleuts of the commander islands and its implications for the
genetic history of beringia.
Olga A. Derbeneva,1 Rem I. Sukernik,1
Natalia V. Volodko,1 Seyed H. Hosseini,2
Marie T. Lott,2 and Douglas C. Wallace2
Laboratory of Human Molecular Genetics, Institute of Cytology and
Genetics, Siberian Division, Russian Academy of Sciences, 10 Lavrent'ev
Avenue, Novosibirsk 630090, Russia.
The Aleuts are aboriginal inhabitants of the Aleutian archipelago,
including Bering and Copper (Medny) Islands of the Commanders, and seem to
be the survivors of the inhabitants of the southern belt of the Bering
Land Bridge that connected Chukotka/Kamchatka and Alaska during the end of
the Ice Age. Thirty mtDNA samples collected in the Commanders, as well as
seven mtDNA samples from Sireniki Eskimos in Chukotka who belong to the
Beringian-specific subhaplogroup D2, were studied through complete
sequencing. This analysis has provided evidence that all 37 of these
mtDNAs are closely related, since they share the founding haplotype for
subhaplogroup D2. We also demonstrated that, unlike the Eskimos and Na-Dene,
the Aleuts of the Commanders were founded by a single lineage of
haplogroup D2, which had acquired the novel transversion mutation 8910A.
The phylogeny of haplogroup D complete sequences showed that (1) the D2
root sequence type originated among the latest inhabitants of Beringia and
(2) the Aleut 8910A sublineage of D2 is a part of larger radiation of
rooted D2, which gave rise to D2a (Na-Dene), D2b (Aleut), and D2c (Eskimo)
sublineages. The geographic specificity and remarkable intrinsic diversity
of D2 lineages support the refugial hypothesis, which assumes that the
founding population of Eskimo-Aleut originated in Beringan/southwestern
Alaskan refugia during the early postglacial period, rather than having
reached the shores of Alaska as the result of recent wave of migration
from interior Siberia.
PMID: 12082644 [PubMed - indexed for MEDLINE]
Am J Hum Genet.
2002 Aug;71(2):415-21. Epub 2002 Jun 25
Link for a full article:
http://www.pubmedcentral.gov/articlerender.fcgi?tool=pubmed&pubmedid=12082644
Mitochondrial DNA variation and the origins of the
Aleuts.
Rubicz R, Schurr TG, Babb PL, Crawford MH
Department of Anthropology, University of Kansas, Lawrence, KS 66045, USA.
The mitochondrial DNA (mtDNA) variation in 179
Aleuts from five different islands (Atka, Unalaska, Umnak, St. Paul, and
St. George) and Anchorage was analyzed to better understand the origins of
Aleuts and their role in the peopling of the Americas. Mitochondrial DNA
samples were characterized using polymerase chain reaction amplification,
restriction fragment length polymorphism analysis, and direct sequencing
of the first hypervariable segment (HVS-I) of the control region. This
study showed that Aleut mtDNAs belonged to two of the four haplogroups (A
and D) common among Native Americans. Haplogroup D occurred at a very high
frequency in Aleuts, and this, along with their unique HVS-I sequences,
distinguished them from Eskimos, Athapaskan Indians, and other northern
Amerindian populations. While sharing several control region sequences
(CIR11, CHU14, CIR60, and CIR61) with other circumarctic populations,
Aleuts lacked haplogroup A mtDNAs having the 16265G mutation that are
specific to Eskimo populations. R-matrix and median network analyses
indicated that Aleuts were closest genetically to Chukotkan (Chukchi and
Siberian Eskimos) rather than to Native American or Kamchatkan populations
(Koryaks and Itel'men). Dating of the Beringian branch of haplogroup A
(16192T) suggested that populations ancestral to the Aleuts, Eskimos, and
Athapaskan Indians emerged approximately 13,120 years ago, while
Aleut-specific A and D sublineages were dated at 6539 +/- 3511 and 6035
+/- 2885 years, respectively. Our findings support the archaeologically
based hypothesis that ancestral Aleuts crossed the Bering Land Bridge or
Beringian platform and entered the Aleutian Islands from the east, rather
than island hopping from Kamchatka into the western Aleutians.
Furthermore, the Aleut migration most likely represents a separate event
from those responsible for peopling the remainder of the Americas, meaning
that the New World was colonized through multiple migrations.
PMID: 15018033 [PubMed - indexed for MEDLINE]
Hum
Biol. 2003 Dec;75(6):809-35
|
|