Gene quest hots up

Geneticists in Iceland have created what they say is the most accurate map yet of the human genome. Researchers at deCODE genetics in Reykjavik used the genetic profiles of 146 Icelandic families to fine-tune the draft map published last year by the publicly funded Human Genome Project. They say the new map is five times as accurate as the draft. It includes 5000 “microsatellite” markers and two million single nucleotide polymorphisms—variations at the level of single DNA bases, which influence people’s susceptibility to disease and response to drugs.