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Photo of Kari Stefansson KARI STEFANSSON

Kari Stefansson, M.D., Dr. Med., is president and CEO of deCode Genetics in Reykjavik, Iceland. He was previously Professor of Neurology, Pathology (Neuropathology), and Neuroscience at Harvard Medical School, and Chief of the Division of Neuropathology at Beth Israel Hospital in Boston. Stefansson received both an M.D. and Dr. Med. from the School of Medicine at the University of Iceland. He trained in neurology and neuropathology at the University of Chicago where he joined the faculty in 1983; when he left the University in 1993 to join the faculty at Harvard, he was Professor of Neurology and Pathology (Neuropathology) and a member of the Committees on Immunology and Neurobiology.

deCode Genetics is a genomics company that searches for disease genes in the Icelandic population. Until recently, the understanding of the genetic basis of human disease was fairly limited and was confined to classic genetic diseases such as hemophilia and cystic fibrosis. Although research into genetic disease established the concept that certain DNA sequence variations could have a huge impact on individual health, this principle could not be extended to more mainstream diseases such as cancer or diabetes. With the advent of the DNA sequencing and mapping technologies (sequencing is the establishment of the order of nucleotides along a piece of DNA; mapping assigns an order to large genomic fragments so that they can be efficiently sequenced), scientists are now able to more closely study genetic variations between individuals.

The hunt for disease genes begins by choosing a target disease such as osteoporosis or schizophrenia, whose genetic contribution in unknown. Family groups are then identified in which these disease genes are statistically more prevalent than in the general populations. Blood samples are collected from these individuals and their DNA is analyzed in order to identify regions of the genome that are linked to the disease.

The Icelandic population offers an unparalleled opportunity to study disease genetics for the following reasons:
  1. Genetically homogeneous population
  2. Genealogy of population since 1800 available to deCode, including health records.
  3. Broad representation of genetically based diseases, for example, certain cancers, Multiple Sclerosis and cardiovascular disease.

See Kari Stefansson's answers to Ask the Scientists questions.


Scientific American Frontiers
Fall 1990 to Spring 2000
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