Dan Gross/The Gazette John Compton and Sherri Bale, former NIH researchers, founded a company that tests for rare disorders. Gaithersburg-based GeneDX has seen its business soar in five years.

Less than one in 100,000 people worldwide are born with Sjögren-Larsson Syndrome, an incurable inherited disorder that begins to show within a baby's first year of life. Though not lethal, the disease causes neurological problems, including speech abnormalities and mental retardation, dryness of skin and short stature.

GeneDx, a five-year-old Gaithersburg biotechnology company, is one of the only companies in the world that will test a patient's genes for SLS. It is one of the rarest diseases the company tests for, even if a positive diagnosis can only confirm a doctor's suspicions, not provide treatment.

This, it turns out, is one of the most common reasons patients turn to GeneDx, says John Compton, a company co-founder.

"It was a surprise to us, but it makes sense now," he says. "The uncertainty, the symptoms. They don't feel good, and they just want to know what they have, even though it doesn't provide any better way of treatment."

Compton and colleague Sherri Bale, both former researchers of inherited skin diseases at the National Institutes of Health, started the company with the mission to provide the benefits of medical research results to the general public.

Using the same genetic testing methods Compton and Bale used at NIH, GeneDx provides testing and diagnosis of inherited rare disorders.

Findings from the tests help patients and physicians make decisions, for example, in family planning or course of treatment.

Working at NIH, Compton and Bale tested the genes of hundreds of patients to identify which genetic mutations caused certain diseases.

Though their findings helped make headway in the development of treatments, as researchers they were not certified to release their results to patients.

"A lot of our patients wanted that information ... but our mandate was to do research," said Compton, who has a doctorate in biophysics.

In March 2000 Compton, 56, and Bale, 50, left NIH and, with $30,000, stepped away from research and into a diagnostic line, for which there was great demand.

"Nobody was doing this, and there was a pent-up demand for this sort of service," said Compton, who in his spare time is mayor of Washington Grove.

In its first year, GeneDx conducted 150 tests and garnered $180,000 in revenues. The number of tests rose to 1,200 in 2001 and 2,400 in 2003.

Last year, the company conducted 3,600 tests and posted revenues of almost $4 million.

Costs for testing range from $350 to $3,900, depending on the complexity and size of the gene to be tested, said Bale, who has a doctorate in human genetics. The company now provides 100 different tests, and is constantly asked to develop more, she said.

"We never would have predicted the level of success from a financial standpoint," she said. "The need out there was far greater than we expected."

Robert Eaton, president of MdBio, a nonprofit that provided funding to GeneDx, calls it "a great company. ... They started with very little, if any, business, and have grown at a very high rate."

GeneDx now has close relationships with various physicians who frequently treat rare disorders.

About 20 percent of the tests the company conducts are to support research laboratories, including labs at NIH.

The company is testing patients for one of Compton's and Bale's former colleagues at NIH, for example, who is researching a rare disorder called periodic fevers and looking for genes that might cause the disease.

If GeneDx finds mutations on a gene that is already known to cause the disease, "that helps the patient, but he wouldn't want to use that in his research," Compton said. "But if it's not ... then he's interested."

Competition in the field of genetic diagnosis has remained relatively low, in part because there is such a vast number of disorders that can be tested, Compton and Bale say.

"It's a very large pie, and I think we can cut it into pieces without grabbing each other's pieces," Bale said.

Most of the disorders GeneDx tests for do not have common mutations, which means that instead of looking at one spot on the gene, scientists must scan the entire gene, she said.

"That is what we're good at," so it's unlikely that other companies would try to get a hand in their field.

Eaton, whose organization provides support for Maryland bioscience companies, says a growth in the number of private companies like GeneDx is inevitable, "as personalized medicine advances and we have more and more genetic marks."

The founders have had a few "nibbles" from interested buyers, with two serious offers, said Bale.

The company, which moved to an office on Perry Parkway two and a half years ago, now has 27 employees, seven with doctorates and three with master's degrees.

From the beginning, Compton and Bale also have handled the business management side of the company, which has included taking on health insurance companies to convince them to cover previously unheard of tests.

In Compton's opinion, the business side of GeneDx has been "easy" so far, mainly because of its success, he said, but as the business continues to grow, management becomes more complicated.

The two key challenges in delivering information, he said, have been to ensure good quality data, and to avoid making human error.

Bale, instead, says the biggest challenge has been keeping up with the growing demand for new tests, and finding the time to add them.