A new step toward treating muscular dystrophy may lie in the discovery of a new form of a nervous system protein which in mutated forms causes the disease.

Louis M. Kunkel, professor of pediatrics and genetics at the Medical School, reports in Saturday's issue of Nature Genetics the discovery of a new form of dystrophin, present only in the peripheral nerve and Schwann cells. These cells protect the nerves and ensure impulse conduction.

"It's a short dystrophin...one fourth the normal size," Kunkel said, "but it has what we believe is the most important part of the protein." Kunkel said this "most important part" probably serves to anchor the full protein in the muscle cell.

This particular form of dystrophin is not usually affected in muscular dystrophy. If the protein were produced in large enough quantities it might be able to take over the functions of abnormal dystrophin present in muscular dystrophy, and partially counteract the effects of the disease.

Producing more of the new form of dystrophin would involve "turning on" its genes at higher levels.

Further study into this method is necessary, Kunkel said. "Generally, it's very hard to turn these on, but we can't say no until we know more," he said.