If 1 million Estonians are genotyped within five years, as officials predict, Estonia will own the behemoth of population genotyping projects, the only one with a database sized in terabytes. The Estonian Genebank Foundation officially opens in March in the city of Tartu. Part of the genebank foundation's mission is to sign up international partners, chiefly research institutes and biotech and pharmaceutical companies. Which diseases the 10,000-patient pilot project will focus on hasn't been decided, but the search for volunteers will take advantage of patient group registries for cancer, Parkinson's disease, osteoporosis, and diabetes. When many genes influence an illness, as in heart disease, cancer, and diabetes, population genotyping is preferable to family studies.
Family studies work well when a single gene underlies a disease.
They rely on linkage analysis, where researchers find genetic markers matching disease inheritance patterns, and then use the markers to map the chromosomal region containing the gene as the first step toward its isolation. With polygenic diseases, where individual alleles seldom sharply increase the relative risk of disease, correlating genetic markers and inherited predisposition to disease requires genotyping hundreds or thousands of people. De-emphasizing those records is in part because nearly 30 percent of Estonia is Russian speaking, reflecting recent era immigration and family records carrying back only a generation or two. Finding genes exerting relatively small effects on diseases means scanning the entire genome. What is lacking is consensus on which ones to use, a matter of economic as well as scientific importance.