Genomes on ice

Heather Pringle reports from a mummy meeting in San Diego some news about Ötzi the Iceman. Most interesting: we’ll soon see his genome.

Also at the meeting, researchers led by geneticist Angela Graefen of the Institute for Mummies and the Iceman reported that they have succeeded in sequencing the Iceman's whole genome, despite the highly fragmented nuclear DNA. The genome has already revealed some surprises. One preliminary finding shows that the Iceman probably had brown eyes rather than the blue eyes found in many facial reconstructions done by artists. Graefen and her colleagues are also examining the DNA to see if tzi possessed genetic predispositions to diseases such as arthritis, which other researchers have diagnosed based on radiological and other evidence.

That actually makes me feel a little better; blue eyes should have been rare, more so in SE Europe. This gene is one where even a single genome carries a lot of potential to reject hypotheses about recent selection. There’s an awful lot we can learn from a single genome.

Lynnerup calls this new line of genetic research on the Iceman "a major milestone." Molecular anthropologist Christina Warinner of the University of Zrich agrees, but she thinks the best is yet to come. Last year, she notes, a research team sequenced another ancient human genome from a 4000-year-old human hair preserved in Greenland's permafrost. "The real jump forward [in understanding the antiquity of some inherited diseases] will happen when we have not just one or two ancient genomes, but hundreds, she says. "Technologically, this isn't very far off, but we're still at the beginning of this process."

Multiple Neoltihic-era genomes wouldn’t be an open window in to the past - they’d be like every garage door in the city was left open. Inherited diseases are one interesting angle, but really one of the most difficult ones because the causative alleles are mostly rare.