Oculopharyngeal Muscular Dystrophy (OPMD)
In 1986, MDA-supported scientists identified the gene that, when defective, causes Duchenne muscular dystrophy. Since then, researchers have forged ahead to isolate and characterize genes involved in almost all the neuromuscular disorders in MDA’s program, including those responsible for oculopharyngeal muscular dystrophy (OPMD). These discoveries have enabled scientists to understand variations among different forms of the diseases and have helped doctors to provide more accurate diagnoses.
Now that this essential first step is almost entirely accomplished, MDA is exploring ways to correct muscle problems caused by the different gene defects. Areas of especially active research include:
- Gene therapy — a mechanism for supplementing defective genes with healthy genes in the tissues affected by neuromuscular disease;
- Gene silencing — turning off genetic instructions that cause the production of toxic proteins; and
- Cell therapy — transplanting new muscle cells, using stem cells or immature muscle cells from a donor or genetically corrected cells from the patient’s own body.
At the same time, other MDA-supported scientists are studying ways to preserve muscle despite the presence of a degenerative disease. As of 2010, some scientists are concentrating on preserving muscle by interfering with a protein called myostatin, a natural inhibitor of muscle growth. Others are studying the biochemical signals that favor muscle repair, maintenance and regeneration, with the aim of improving those functions.
MDA-supported researchers are probing the causes of OPMD at the molecular and cellular levels, with an eye to identifying targets for therapeutic development.
For instance, they're trying to figure out precisely how abnormalities in the PABPN1 protein (see Causes/Inheritance) cause problems in skeletal muscles and are investigating the possibility that abnormal PABPN1 proteins may affect genes important for muscle function.
For more on OPMD, including research in this disease, see In Focus: Oculopharyngeal Muscular Dystrophy (OPMD).