On the Trail of Rare Diseases

Tuesday, January 2, 2001
By Terence Chea ,
Washington Post Staff Writer

URL: http://www.washtech.com/news/biotech/6266-1.html

Date accessed: January 7, 2001

Millions of Americans suffer from rare hereditary disorders caused by defective genes, leaving them with conditions ranging from scaly skin to sporadic fevers to mental retardation.

Yet despite the prevalence of these genetic disorders, there are few places where patients can find out if they carry a disease-causing gene or whether they will pass it on to their children.

Sherri Bale and John Compton, the founders of GeneDx Inc. of Rockville, are trying to change that. Last year, the two geneticists left their jobs at the National Institutes of Health in Bethesda to start a genetic testing company specializing in rare hereditary disorders. Scientists have identified about 6,000 such disorders, which are known as "orphan" diseases because each disorder affects fewer than 200,000 Americans.

GeneDx designs and performs diagnostic tests for rare disorders characterized by a single genetic mutation. The company, which until recently employed only Bale and Compton, analyzes tissue samples sent by physicians and genetic counselors around the world to determine whether a patient carries a disease-causing mutation.

"It can confirm a diagnosis, which is important for treatment as well as the future handling of an individual's condition," said Compton, GeneDx's chief executive and scientific director. "It can determine whether you have a genetic disease you'll be passing on to your offspring."

When they first started, Bale and Compton focused mainly on hereditary skin disorders, their specialty. But in the past 10 months, they have branched out into diseases such as rheumatological and connective-tissue disorders. They have developed and performed tests for more than 25 diseases, including 18 tests that they say are offered nowhere else.

"We believe this is the kind of knowledge that will reduce medical expense and medical problems," Compton said. "Our mission is to provide absolutely accurate information so that patients can make informed decisions."