from the ethical-dilemmas dept
The population of Iceland is unusual in a number of ways. Icelanders are descendants from a relatively small group of early settlers that remained isolated for hundreds of years. They have unmatched genealogical records that allow the family tree of many Icelanders to be traced back a thousand years, and thus for familial interrelationships on the island to be established with unprecedented completeness. Put those together, and you have a population that offers unique advantages for studying human genetics. That fact led to the founding of the Icelandic company Decode, which was set up in the hope that it would be possible to use Iceland's population to pinpoint genes associated with medical conditions, and then come up with new ways of diagnosing, treating and preventing them.
That didn't work out, and in 2012, Decode was bought by Amgen. But technology has advanced hugely since Decode's founding in 1996. The cost of sequencing the human genome has fallen dramatically, allowing the DNA of thousands of people to be compared -- something prohibitively expensive 20 years ago. The New York Times reports on research by Decode that has resulted in the sequencing of the genomes of 2,636 Icelanders, the largest collection ever analyzed in a single human population. Because of the completeness of Iceland's genealogical records, Decode's scientists were able to do something rather remarkable: work out the full genomes of another 100,000 Icelanders, a third of the entire country, without collecting any of their DNA.
With a technique called imputation, the researchers say they are able to ascertain the full genomes of people they have not even examined. Dr. Stefansson said that means that his firm could generate a report for genetic disease on every person in Iceland.
Once those "imputed" genomes have been constructed using computers, they can be interrogated in novel ways:
With the push of a button, for instance, the firm can identify every person with the well-known BRCA2 mutation, which dramatically raises the risk of breast and ovarian cancer -- even if they have not submitted to genetic testing themselves.
That raises an interesting ethical question. Should people who have never had their genome sequenced be told the results of this kind of computer-based analysis? Although the Icelandic case might seem unique, it is only a matter of time before sequencing costs fall so far that millions, rather than thousands of individuals can be sequenced within a population. And the more genomes that are available, the more imputed genomes that can be calculated, making the ethical dilemmas faced in Iceland something that people in other countries will soon have to confront too.
Currently, that information is withheld from Icelanders, but Dr. Stefansson hopes that the government will change its policy. “It’s a crime not to approach these people,” he said.