Scientists Locate CTG Gene

Science has made a giant step towards finding the cure for muscular dystrophy, MIT researchers said yesterday.

At a press conference announcing the publication of results in the February 21 issue of Cell magazine, MIT scientist J. David Brook said that his team had located the gene that leads to the disease's most common form, myotonic dystrophy.

Currently, 30,000 Americans are afflicted with the hereditary disease, which causes muscles to waste away. Sufferers often die in their fifties and sixties of heart disease or respiratory failure.

The researchers found, through a process called gene mapping, that the repetition of a nucleotide sequence triplet, CTG, is the cause of the disease. The sequence is present in most people, but researchers demonstrated that it is significantly more abundant in myotonic dystrophy sufferers.

Fifty repetitions are necessary for symptoms of the disease to arise, and an increase in the number of repetitions is reflected by an increase in the severity of the disease, scientists said.

The announcement was made by Brook and fellow researchers Richard T. Moxley, from the University of Rochester, Duncan J. Shaw, from the University of Wales College of Medicine, and Keith Johnson, from Charing Cross and Westminster Medical School.

A Cure May Be Possible

The discovery will eventually allow doctors to provide more useful genetic counseling and may even lead to a cure, said Moxley.

"Whenever you make a fundamental breakthrough like this, things which once seemed disparate suddenly gel together," Moxley said.

Muscular dystrophy sufferers yesterday said they are looking forward to the cure the discovery may bring.

Anne M. Crystal, who attended yesterday's conference, said she hopes the future will hold the cure for her severely affected two-and-a-half year old son. Crystal herself is mildly affected by the disease.

"He's only two," said McCrystal. "With the progress in the field now, maybe 10 years down the road they'll have the answer."

The research was partially funded by the Muscular Dystrophy Association. Brooks is a postdoctoral fellow in the laboratory of MIT professor David E. Housman, who announced earlier this month that muscular dystrophy was linked to an enlarged and unstable area of the same chromosome on which CTG appears.