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Category Archives: chicken DNA

Ancient DNA… of chickens

Sure, why not?
Alice A. Storey, Investigating the Global Dispersal of Chickens in Prehistory Using Ancient Mitochondrial DNA Signatures. PLoS ONE, 2012. Open access ··> LINK [DOI: 10.1371/journal.pone.0039171]
The authors managed to produce more or less reliable mtDNA haplotypes for 48 remains of historical and prehistorical chickens from Thailand, Pacific Islands, Latin America (a pre-Columbian site in Chile but post-Columbian sites elsewhere) and (medieval) Spain.
Excepting the oldest Thai haplotype, all them belonged to haplogroups D and E, as follows:

Fig. 1
In spite of the authors burying most of the relevant data in the supplemental material, I was able to conclude that the ancient haplotypes (ah) above mean in terms of samples:
  • Haplogroup E:
    • cluster 1:
      • ah1 Pacific Is. (n=1)
      • ah2 Pacific Is. (n=4), Thailand (n=1), Chile (n=1)
      • ah6 Peru (n=1)
    • cluster 2:
      • ah3 Pacific Is. (n=10), Chile (n=2), Spain (n=3), Haiti (n=1), Florida (n=1)
      • ah4 Spain (n=1)
      • ah5 Bolivia (n=3)
      • ah7 Spain (n=1)
  • Haplogroup D:
      • ah9 Pacific Is. (n=1), Peru (n=1)
    • cluster 3:
      • ah10 Pacific Is. (n=14)
      • ah11 Pacific Is. (n=1)
  • Haplogroup B (not shown):
      • ah12 Thailand (n=1)
There is no ah8 apparently. 
It must be noted that the ah9 haplotype from Peru is very early post-Columbian, from before 1600 CE, making it another likely evidence of Polynesian introduction of chicken in South America, along with the Chilean sites (which allow for no other explanation). However the Peruvian haplotype is more related to Micronesia than to Hawaii or Rapa Nui.
Other 17th century samples from Bolivia and Peru (ah5 and ah6) have no obvious connection with either plausible origin. Instead Caribbean sites are probably related to Spain.
A simplified geographical distribution is also offered (oddly enough on a pre-WWI map):

Fig. 2

The authors conclude:
As a result of the careful analysis of archaeologically associated, and
in some cases directly dated, ancient DNA samples an early global
distribution of haplogroup E chickens has been revealed. This dispersal
out of Asia began before 3000 years ago and involved the movement of
chickens both westwards to Europe and eastwards into the Pacific. The
distribution of haplogroup D likely represents a separate dispersal into
the Pacific from a distinct Asian domestication centre. The eventual
identification of these centers will greatly enrich our understanding of
chicken domestication and the history of dispersals from multiple
locations. While unambiguous data does not yet exist to trace any of the
detected mtDNA signatures back to specific domestication centers, the
analysis of ancient DNA sequences presented here is an important first
step towards it. Future research needs to focus on markers identified,
from both full mtDNA genomes and nuclear genes which are subsequently
targeted in ancient specimens, examined within their historical and/or
archaeological context.
 
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Posted by on July 26, 2012 in aDNA, America, chicken DNA, mtDNA, Neolithic, Oceania, SE Asia