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Iceland's record of low immigration and its genealogical records going back 1,000 years make it a paradise for geneticists. A third or more of the population has already donated a DNA sample - but a new push to increase that figure is meeting some resistance.

"No!" says Alda Sigmundsdottir, raising her voice and waving her arms around emphatically.

"I will not be emotionally blackmailed into giving my DNA - it's my own private and personal information and I am not going to give it to anybody!"

Icelandic writer and journalist Alda and I are sitting in my hotel room in Reykjavik, talking about her latest blog in which she describes the attempt of the country's leading genetics company deCODE to recruit volunteers to give DNA samples. The company already has over a third of Icelanders in its database but now it wants to double its count.

Earlier this summer, it sent out swab packs in the post with information informing households that couriers would be knocking on doors in the near future to collect the samples from willing participants.

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The couriers turned out to be volunteers from the renowned and respected organization ICE- SAR, Icelandic Search and Rescue, whose team members regularly risk their own lives to save others in peril in the dangerous Icelandic landscape. For every sample ICE-SAR collected, deCODE promised to offer a $20 donation to the charity.

"It puts a lot of pressure on people," explains Alda. "You sort of feel like you're a bad person - you know, if I don't give my sample, ICE-SAR doesn't get my donation. And I resent that kind of manipulation."

Image copyright Alda Sigmundsdottir

From my hotel window I can see deCODE's headquarters. It's a low slung, unassuming, dark grey building next to the university complex, but when I go to visit it, it takes me more than five minutes to get through the security system.

DeCODE's director, Dr Kari Stefansson, is not in the building as I tour it and he has forbidden his staff to answer any of my questions in his absence - even basic inquiries such as how many people work in the building go unanswered. On my oddly silent tour of the offices, I catch glimpses of laboratories, legal departments and a vibrant canteen.

"No-one is forcing anyone to give their DNA," snaps Kari when we catch up over Skype. "And the National Biotheics committee suggested we use third parties to approach potential participants. But there is nothing wrong trying to convince people to take part in biomedical research. Without making discoveries about the nature of disease, we are not going to advance medicine and we are in a privileged position in Iceland. "

It was back in the mid-90s that Kari first realised the potential of mining Iceland's gene pool. With little significant immigration since the Norsemen first settled here in the 9th Century, Iceland is among the most homogeneous nations on earth. With so little background noise to filter in the small population of just 320,000 people, it's much easier for scientists to isolate faulty genes than it is in larger multi-ethnic countries such as Britain or the US. Iceland also has a database containing the genealogy of the entire nation dating back 1,100 years.

Icelanders at a glance

Image copyright Getty Images

First settlers arrived in the 870s - 60-80% of them were of Nordic stock from Norway, the rest mainly Celtic

Settlers brought their language - Old Norse - from Norway, which has evolved into modern Icelandic

The first comprehensive census in Iceland was taken in 1703, at which time 50,358 people were reported, today the population is 328,000 (UN, 2012)

Large-scale emigration to the US and Canada occurred at the end of the 19th Century and beginning of 20th Century

BBC country profile

Encyclopedia Britannica

"We are probably the most productive entity in human genetics in the entire world," insists Kari. "For example we have recently published a mutation which provides almost complete protection against Alzheimer's disease. Most Icelanders support us in our work."

In Iceland everyone knows everyone and when you give your DNA sample, you are not just giving information about yourself Salvor Nordal, University of Iceland

A short walk away from deCODE at her office in the University of Iceland, Salvor Nordal, director of the Ethics faculty, says deCODE has prompted many a debate in her department. I ask her whether it's fair to argue that in a country where the gene pool can be mined so effectively, Icelanders have a responsibility and a duty to provide a DNA sample to avoid health risks in the future.

"Of course one can argue that," she smiles. "But you also need to remember that in Iceland everyone knows everyone and when you give your DNA sample, you are not just giving information about yourself."

She reminds me about Iceland's genealogy database and points out that deCODE's geneticists can use computational methods to calculate the odds of whether an individual carries a particular genetic variant without directly sequencing their DNA, if it knows the DNA of that individual's relatives.

"They can fill in the missing gaps," says Salvor. "deCODE has collected so much information that we might become the first nation to be genome sequenced. Now it becomes much more than asking questions about an individual's privacy - we are talking about group privacy… and whether we can be discriminated against as a member of that group."

Image copyright Science Photo Library

She asks if I remember the media hype last year surrounding Angelina Jolie's decision to have a double mastectomy when doctors told her she carried the faulty BRCA1 gene giving her a high possibility of contracting breast cancer.

"In Iceland we have never had a proper debate about whether individuals who give samples should be notified if they have a risk of cancer for example. Who would want to know? Who wouldn't?" she asks.

My only goal is - not manipulating the human genome - but finding out which variant genes are behind the common diseases of man Kari Stefansson, Decode

Unlike the UK's Biobank, which is a charitable and government-funded venture, deCODE is a private enterprise. Having struggled financially, the firm is now owned by the American biotech giant, Amgen. The thought that a foreign company might profit from their private information has made many Icelanders baulk.

"It makes me very nervous," journalist Alda Sigmundsdottir admits. "I'm thinking the DNA of 100,000 or so Icelanders is probably quite a valuable commodity for a multi-national corporation. If a university, say the University of Iceland, was conducting the research and the findings were available to academic institutions all over the world, I wouldn't hesitate to give a sample. That's how it should be done. Not by a private company using it to profit."

Kari insists that all DNA in his possession is labelled with encrypted IDs and is fiercely protected. Amgen has no direct access to the data.

More from the Magazine Image copyright National Archives of Iceland In 1974, police launched one of the biggest murder investigations Iceland has ever seen. The case was eventually solved when six people confessed to their parts in the murders of two men whose bodies have never been found. Forty years on, a government review has found that the confessions were unreliable and a campaign is underway to quash the convictions. But some of those who were wrongly convicted are struggling to accept their innocence. Simon Cox investigates. The Reykjavik Confessions

"A private company is much less likely to abuse a system than a government," he tells me firmly. "If we violate the rules, we could be closed down with the stroke of a pen. If a government owned the database and abused it, it would be impossible to close down a government."

He pauses and then adds: "Keep in mind my only goal - it is not manipulating the human genome but finding out which variant genes… are behind the common diseases of man."

To further assist in this effort, until 10 years ago, deCODE even had guaranteed access to every Icelander's health records, thanks to a decision taken by the Icelandic Parliament. Then in 2003, a woman sued to keep her deceased father's medical records from going into the deCODE database, citing a right to privacy. Now the company has to approach individuals for their consent.

On my way back from deCODE, I chat to people lunching at the university cafeteria and ask if they have given a DNA sample to deCODE. Almost all of them have done so, and shrug when I ask them if they had concerns about privacy.

One man in his mid-40s is emotional as he replies to me and his soup-spoon trembles as he talks.

"I have a family member with a genetic condition who has suffered a lot," he tells me quietly. He meets my gaze.

"Why should he suffer a lot if we know we have information that can help him? What is it to do with privacy?"

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