Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, September 8, 1994 TAG: 9409080099
SECTION: NATIONAL/INTERNATIONAL PAGE: A-7 EDITION: METRO
SOURCE: Los Angeles Times
DATELINE: LENGTH: Medium
The feat marks the first time researchers have used new technology developed for the human genome project - the ambitious effort to map the complete human genetic blueprint - to develop the genetic profile of a complex disorder in which multiple genes interact with environmental factors to produce disease.
``The technology we have developed here not only helps diabetes, but is also going to play a role in understanding [the genetic basis of] heart disease, asthma, rheumatoid arthritis and certain types of cancers,'' said geneticist Simon T. Bennett of Oxford University. ``This is a major step forward.''
Researchers have long known that genes contribute to diabetes, but their role is different than in a simpler genetic disorder, such as muscular dystrophy or Lou Gehrig's disease, where a single gene is involved. Diabetes, like heart disease, cancer and many other disorders, is polygenic - meaning several genes, each of different importance, play a role in its onset. The individual must also be exposed to a trigger in the environment - a virus or a protein in cow's milk, in the case of diabetes - before the disease occurs.
Molecular geneticist John Todd and colleagues at Oxford used techniques of high-speed replication of DNA (the PCR technique used in DNA fingerprinting), computerized control of the separation of DNA fragments, and automation to dramatically speed up the medical sleuthing.
They identified 300 genetic markers in thousands of blood samples from 300 U.S. and British families with a history of one type of diabetes. From these studies, they were able to show that 18 separate genes figure in the onset of the disease.
by CNB