April 21, 2009

Muscular dystrophy gene is identified

U.S. medical researchers say they have identified a specific gene involved in facioscapulohumeral muscular dystrophy and its related vision problems.

FSHD, also known as Landouzy-Dejerine syndrome, is the world's third most common type of muscular dystrophy, characterized by progressive skeletal muscle weakening in the face, shoulders and upper arms. And more than half of Landouzy-Dejerine patients also have abnormal blood vessels in the back of the eye, which can cause vision problems.

University of Illinois scientists said more than 95 percent of Landouzy-Dejerine patients carry a genetic abnormality they hypothesized might affect expression of the FRG1 gene. Previous frog studies showed it is important for skeletal muscle development. Therefore, the University of Illinois scientists investigated the possibility that gene might also be responsible for the blood vessel abnormalities in Landouzy-Dejerine patients' eyes.

They said they studied the FRG1 gene in frogs and found the protein it encodes for is highly expressed in blood vessels. Additional experiments showed normal FRG1 protein expression is important for blood vessel growth and organization.

The scientists said their findings support their hypothesis that FRG1 expression is a main cause of that type of muscular dystrophy and might be an important target for therapeutic intervention.

The study by Ryan Wuebbles, Meredith Hanel, and Peter Jones of appears in the May-June issue of Disease Models and Mechanisms.