Researchers at Fred Hutchinson Cancer Research Center have harnessed the power of yeast - a simple, single-celled organism crucial for brewing beer and baking bread - as a model to study trait inheritance and the genetics of complex conditions and characteristics at the most basic, molecular level.

Fred Hutchinson geneticist Leonid Kruglyak, Ph.D., and colleagues will report their findings in the April 26 edition of Science. Rachel Brem, Ph.D., and Gael Yvert, Ph.D., both fellows in Kruglyak's laboratory, share first authorship of the paper.

Complex traits, which range from diseases like diabetes and cancer to behaviors like violence and aggression, have been notoriously difficult to study in humans and other mammals, the systems in which most such analyses have been conducted.

While yeast provides a powerful new avenue for studying natural variation that results from complex genetic interactions, the researchers caution that even in the case of this simple fungus, the study of complex traits is likely to remain a formidable challenge in biology.

"The good news is that our method worked and that we can use it as a way to study complex traits, Yvert said. "We can expand it to the study of other organisms. The caution is that we're still dealing with a very complex system that is likely to be even more so in humans."

"Complex" diseases of civilization typically arise from a variety of inherited and acquired mutations in more than one gene. Identifying the many genetic factors underlying conditions such as cancer and heart disease poses a much bigger challenge to geneticists than rare disorders such as Huntington's disease and cystic fibrosis, which are always traceable to a single genetic defect.

To date there have been no complex diseases or inherited traits in humans for which all of the causal genetic factors have been identified. Finding multiple genetic regions implicated in any one disease or trait has been difficult because the
'"/>

Contact: Kristen Woodward
kwoodwar@fhcrc.org
206-667-5095
Fred Hutchinson Cancer Research Center
22-Apr-2002