The Genetic Genealogist

Yesterday Science published a report from deCODE genetics in Iceland and a second report from academic colleagues in the United States and Canada that announced the discovery of a gene variant (a SNP) on chromosome 9p21 that results in an increased risk of heart attack (the abstracts are available online here and here). The SNP was discovered through genome-wide SNP analysis in Iceland and replicated in three groups of European descent in the United States. I don’t have access to either paper, but according to deCODE’s press release the variant is estimated to account for 20% of the incidence of heart attacks in Europeans, including one-third of early-onset cases (men and women age 50 to 60). Both companies used SNP Chips (that’s fun to say outloud), tiny gene chips that contain thousands and thousands of SNPs across the entire genome. Want to learn more about SNPs? Go to the SNP information page at the Human Genome Project.

deCODE genetics “is a global leader in gene discovery – our population approach and resources have enabled us to isolate key genes contributing to major public health challenges from cardiovascular disease to cancer, genes that are providing us with drug targets rooted in the basic biology of disease.” The company plans to “bundle this discovery with other genetic variants it has linked to risk of heart attack into a DNA-based test for gauging inherited risk of [heart attack].”

You can read more about this latest discovery at the New York Times, and at Eye on DNA, an interesting and educational blog that follows all the latest developments in genetics. Whenever I sit down to write about the latest genetic discovery in the news, I have to go to Eye on DNA to make sure there’s something left to write about!

So what does this have to do with genetic genealogy? Part of the reason that deCODE has had so much success in identifying SNPs and genes involved in disease is because of the extensive genealogies and medical histories available to Icelandic researchers. This type of information is a vital part of genetic studies such as this one. Instead of using genetics to explore ancestry, deCODE is using ancestry to explore genetics! At the same time that science is allowing genealogists to expand our knowledge, we genealogists have the opportunity to give something back by recording and maintaining detailed family medical records.

Some interesting facts about Icelandic genealogy:

1. The country’s public health services has maintained detailed individual medical records since 1915.

2. 80% of all Icelandic people who have ever lived can be traced on family trees.

3. There has been very little genetic influence since the Vikings and Celts settled there almost 1200 years ago.