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The Full mtDNA Genome of Ötzi is Sequenced (Twice?)

Großglockner seen from the southwest. The Groß...

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Ötzi the Iceman is the popular name for a 5,000 year-old mummy discovered frozen in the ice of the Alps in 1991.  Studies of the Iceman has revealed an immense amount of information about him, including details of his life, his death, and his culture. 

Although Ötzi’s mtDNA has previously been studied, researchers had only examined short segments which suggested that his mtDNA belonged to Haplogroup K.  A new paper in Current Biology (subscription only darn it) details Ötzi’s full mtDNA genome for the first time:

"Using a mixed sequencing procedure based on PCR amplification and 454 sequencing of pooled amplification products, we have retrieved the first complete mitochondrial-genome sequence of a prehistoric European. We have then compared it with 115 related extant lineages from mitochondrial haplogroup K. We found that the Iceman belonged to a branch of mitochondrial haplogroup K1 that has not yet been identified in modern European populations."

The full sequence (which has been deposited in GenBank with accession number EU810403) was then compared to 115 published full mtDNA Haplogroup K sequences.  The comparison suggests that Ötzi belonged to a previously uncharacterized subclade of Haplogroup K, now termed K1ö.

Strange Conclusions – Otzi has NO living relatives?

Now, as any genetic genealogist knows, when your mtDNA doesn’t match anyone you conclude that you have to wait until more people get tested.  This is especially true if you believe that your relatives would be in continental Europe – for some reason those continental Europeans have very little interest in genetic genealogy.  The authors point out that Ötzi’s mtDNA line might have died out in the past 5,000 years, but they also acknowledge that the comparison database was small and further testing in Europe might reveal more examples of this new subclade.

As Kambiz points out in the comments to his post on this new paper, the media isn’t quite as careful as the authors of the paper.  See "Iceman May Have No Living Relatives" by National Geographic, for example.  Although they do a decent job of discussing the article and all the aspects I mention, the title is so bad that it makes my teeth hurt.

Or Does he?

But see this article: "DNA shows Otzi the Iceman has kin."  According to the article, Alan Cooper – head of the University of Adelaide’s Australian Center for Ancient DNA – has also sequenced Otzi’s mtDNA and stated that "We have found someone very, very closely related."  I’m looking forward to comparing the mtDNA genome obtained by the two research groups.  Will they be the same?

A few points to remember:

  • Ötzi’s mtDNA belongs to a previously undiscovered subclade of Haplogroup K, but there is currently no data to suggest that this subclade has died out in present-day humans.  115 mtDNA genomes barely constitutes a database!
  • Remember that this is only mtDNA testing, which passes only from mother to child.  Even if there is no living person with mtDNA belonging to the K1ö subclade, Ötzi could still have 2 billion direct descendants!

The Paper:  Luca Ermini, Cristina Olivieri, Ermanno Rizzi, Giorgio Corti, Raoul Bonnal, Pedro Soares, Stefania Luciani, Isolina Marota, Gianluca De Bellis, Martin B. Richards, Franco Rollo (2008). “Complete Mitochondrial Genome Sequence of the Tyrolean Iceman” Current Biology, DOI: 10.1016/j.cub.2008.09.028.

HT: Anthropology.net.

Blaine Bettinger

Intellectual property attorney, genealogist, and author of The Genetic Genealogist since 2007