Washington, Apr 23 : Researchers have demonstrated restoration of muscle function in a mouse model of Duchenne’s muscular dystrophy (DMD), with the help of a new drug that has the potential of also countering thousands of other genetic illnesses.

The researchers from the University of Pennsylvania School of Medicine, PTC Therapeutics Inc. and the University of Massachusetts Medical School demonstrated the functioning of the new drug, developed by the South Plainfield, NJ-biotech firm called PTC124, that binds to the ribosome, a cellular component where the genetic code is translated into proteins, one amino acid at a time.

The drug allows the ribosome to read through a mistake in the genetic code called a premature stop codon in order to properly make whole proteins.

“This new class of treatment has the potential to help a large number of patients with different genetic diseases that have the same type of mutation,” said senior author H. Lee Sweeney, PhD, chair of the Department of Physiology at Penn.

In DMD, patients are missing dystrophin, a protein that helps keep muscle cells intact. About 15 percent of DMD patients do not make dystrophin because of the mutation. DMD eventually affects all voluntary muscles, as well as heart and breathing muscles.

PTC124 attaches to ribosomes in all cell types within the MD mouse model, overriding the mutation in the dystrophin gene that tells it to halt production of the protein. Instead of stopping, the full-length dystrophin protein is made. The drug enables enough protein to be made to correct defects in the muscle of the DMD mouse, and at the same time the drug does not prevent the ribosome from reading correct “stop” signals in the genetic code to make other necessary proteins.

“Enough dystrophin accumulated in the muscles of the MD mice so that we could no longer find defects in the muscles when we examined them,” said Sweeney.

“For all intents and purposes the disease was corrected by treatment with PTC124,” he added.

The drug allowed dystrophin to be made in cells in which it was previously absent, to be delivered to the proper location at the cell membrane, and to induce restoration of muscle function in rodent muscles.

The research is available online before its publication in Nature. (ANI)