Gene therapy treats muscular dystrophy in mice

New research may aid Muscular Dystrophy victims Keystone Archive

Scientists in Basel have managed to restore muscle function in mice by replacing a diseased protein with another molecule. The approach might offer a way of treating people with muscular dystrophy and other genetically caused diseases.

The researchers, led by Markus Ruegg, associate professor at Basel University’s Biozentrum, engineered a miniature form of the muscle protein, agrin, to make up for the lack of another muscle protein.

Replacing a disease-causing molecule with another is a procedure that has already been performed in animals with muscular dystrophies. What the Basel team has shown is that the replacement gene need only be similar in function – and not necessarily in structure – to the diseased protein.

“Our work offers a new strategy for treating genetically caused diseases by replacing diseased genes with another functionally related molecule,” Ruegg told swissinfo.

Alleviate symptoms

“The technique also suggests that drugs that raise agrin levels might alleviate symptoms of muscular dystrophy. And it demonstrates how small versions of large proteins can be useful for gene therapy, as they are less likely to cause immunological responses.”

Aspects still being investigated in Basel include how much agrin is needed and whether the full-size agrin also restores muscle function.

The Basel team worked on a variation of congenital muscular dystrophy, a rare condition. The symptoms can be noted at birth, or soon after, in both boys and girls. Children who have the condition are unable to walk or even stand up because their muscles degenerate. Often, they die prematurely from respiratory failure.

The most common form of the muscle wasting disease, Duchenne muscular dystrophy, affects about 30,000 males worldwide. The disease usually begins in early childhood and is often fatal by the age of 30.

The Basel study is reported in the science journal, Nature.

by Vincent Landon