Founder Populations Fuel Gene Discovery.

Isolated people-groups further genetic study

The field of human genetics has never been "politically correct." The first gene screens created in the 1970s, for sickle cell disease and Tay-Sachs disease, targeted African American and Ashkenazi (eastern European) Jewish populations, respectively. This targeting made economic sense as these conditions are more prevalent within these populations. It isn't that genes discriminate, but that the human tendency to select mates like themselves tends to keep particular gene variants within certain groups.

Today, as genetics morphs into genomics, certain populations are again playing prominent roles in gene discovery. These "Founder populations" are modern groups that descend from a few individuals who left one area to settle another for political, religious, or social reasons. Founder populations are sought after for association studies that search for links between health-related gene variants and SNP patterns (profiles of single nucleotide polymorphisms, which are sites within the genome where a single base can differ among individuals).

At the Genome 2001 Tri-conference held in San Francisco this past March, Philippe Douville, vice president and chief business officer of Galileo Genomics Inc. of Montreal explained that "The main recognized Founder populations in the world are those of Quebec, Finland, Sardinia, Iceland, Costa Rica, the northern Netherlands, Newfoundland, and several discrete ethic groups, including the Ashkenazi Jews." In addition to providing useful tools to predict disease susceptibilities, studying Founder groups often turns up fascinating historical facts.

FROM MONOGENIC TO POLYGENIC DISORDERS

Galileo Genomics is one of many biotech start-ups conducting association studies on Founder populations. At Lincoln, Neb.-based GeneSeek Inc., the focus is on the fractured populations of India. "The gene pool goes back 3,000 years. As a consequence of the caste system, with mate selection roles and polyandry and polygyny operating, the whole country is subdivided into subpopulations. There is a lot of restricted gene flow, with breeding isolation and smaller populations with rapid changes for certain traits. [Indians] have unique types of cancers …