In a soccer match against Estonia in 1996, Eiður Smári Guðjohnsen stepped on the field as a substitute for his father Arnór. This marked the first time that a father and son played in the same international match.
It’s no surprise that the Iceland national football team is becoming everyone’s favorite underdog after their recent David and Goliath run at the UEFA European Championships.
As the smallest country to ever make the tournament, they have paved their way to the quarter-finals having defeated the Netherlands twice in qualifying; drawing against world-powerhouse Portugal in round-robin play; and most recently defeating England in the Round of 16.
The Icelandic soccer team is quickly becoming an historic sports story. From a team manager who moonlights as a dentist, to a goalkeeper who doubles as a film director, or the 30,000 Icelanders who traveled to France in support of the team (10% of the country’s population).
While it is not totally unheard of for a father-son duo to play on the same professional sports team, the Guðjohnsen case is particularly interesting. With a population of just 332,529, and a long history of limited immigration, Iceland has become a geneticist’s dream.
The unique population of Iceland offers genetic researchers a rare opportunity to study a uniform group of individuals. Unlike the diversity that is found in many countries, the origins of Icelanders can be traced back to a few common ancestors.
The combination of minimal genetic diversity in the population and exceptionally well-kept genealogical records going back six to eight generations provides scientists a greater promise of uncovering genetic variants that confer disease risk.
In collaboration with the Icelandic government, deCODE Genetics Inc. genotyped over 100,000 Icelanders in the largest genetic study of a single population to date. This work was published in 2015 as a set of 4 academic papers in Nature Genetics. The deCODE group were able to uncover unprecedented insight into several genes that cause human disease, genes that have lost their intended function, and even a look at the most recent common male ancestor.
The low diversity amongst the Icelandic population meant that there was less background noise for deCODE researchers to sift through. They had no trouble identifying meaningful gene variants amidst the 20 million single nucleotide polymorphisms (SNPs, or sometimes referred to as genetic variants) sequenced from each Icelandic participant.
Examples of breakthrough findings include the identification of three SNPs that confer increased risk in diseases of the heart and liver (1), and Alzheimer’s (2). Mutations causing genes to lose function were found in 8,000 healthy participants (3), which could be an excellent starting place for drug discovery. And the final finding is groundbreaking in tracking human evolution. By zooming in on the discrete differences in the genomes of 753 Icelandic men, specifically their unique Y chromosome, deCODE scientists were able to shift forwards the date of our first common male ancestor by 100,000 years (4).
Studying populations like Iceland is changing the landscape by which we carry out genetic research across the world. The Icelandic population-scale genetic study serves as a model for larger, more diverse genetic studies of the human population, and shows the untapped potential that can come out from large-scale genetic sequencing.
Team Athletigen’s Muna Lee once said, “When you look at my size, I’m not that strong. When you look at my data, I’m the strongest. That’s confidence for me.” The same can be said for the smallest country to ever make the European Championships.
- Gudbjartsson, D. F., Helgason, H., Gudjonsson, S. A., Zink, F., Oddson, A., Gylfason, A., … Stefansson, K. (2015). Large-scale whole-genome sequencing of the Icelandic population. Nature Genetics, 47(5), 435–444.
- Steinberg, S., Stefansson, H., Jonsson, T., Johannsdottir, H., Ingason, A., Helgason, H., … Stefansson, K. (2015). Loss-of-function variants in ABCA7 confer risk of Alzheimer’s disease. Nature Genetics, 47(5), 445–447.
- Sulem, P., Helgason, H., Oddson, A., Stefansson, H., Gudjonsson, S. A., Zink, F., … Stefansson, K. (2015). Identification of a large set of rare complete human knockouts. Nature Genetics, 47(5), 448–452.
- Helgason, A., Einarsson, A. W., Guðmundsdóttir, V. B., Sigurðsson, Á., Gunnarsdóttir, E. D., Jagadeesan, A., … Stefánsson, K. (2015). The Y-chromosome point mutation rate in humans. Nature Genetics, 47(5), 453–457.