Icelanders may not have the unique genetic heritage that gene-hunting firm deCODE Genetics had previously claimed, a new study suggests. The Icelandic biotech company is hunting for genes involved in common illnesses, using medical records and DNA samples from its country's people. It claims that Icelanders are more genetically similar than other European people, making it easier to pick out genetic variations associated with disease. But Einar Arnason, a geneticist at the University of Reykjavik, has reanalysed the data upon which this claim was based, and says that at least some stretches of DNA may vary as much in Iceland as they do in the rest of Europe.
According to a news report in Nature last week, Arnason found that the genetic databases used by deCODE when comparing Icelandic DNA to that of other Europeans contained extensive errors. He carried out his own study, comparing DNA from Icelanders with published data on DNA from 26 different European populations, but avoided using databases. His results, based on a comparison of maternally inherited mitochondrial DNA, indicate that Iceland displays just as much genetic variation as other European populations.
The Icelandic government granted deCODE exclusive access to the country's medical records, a move which angered many doctors. The pressure group Mannverd, of which Arnason is a member, opposes what it views as the commercial exploitation of Iceland's population. Referring to Arnason's study, deCODE says that the database errors have only a 'limited' effect, and that Iceland's extensive genealogical data will aid the hunt for disease genes, whatever the genetic variation within the country's population proves to be.