Mayo Clinic researchers identify new form of muscular dystrophy in adults

Mayo Clinic researchers have identified a previously unknown form of muscular dystrophy, a group of genetic diseases characterized by progressive weakness and muscle degeneration. This newly identified form develops after age 40 and causes heart muscle damage, limb muscle weakness and nerve damage. The researchers have named the newly defined disorder “zaspopathy” (Zas-PO-path-ee).

Some 50,000 Americans have some form of muscular dystrophy, and there are currently no cures. Mayo Clinic researchers note that their work may help contribute to a cure because it increases the understanding of the muscular dystrophy disease process and the role genes play in it. They say their research is a crucial first step toward discovering treatments, because genes offer a promising target at which aim new therapies. The report on the discovery will appear in the Jan. 26 online version of the journal Annals of Neurology.

The Mayo Clinic researchers found that any one of three mutations in the gene that supplies the instructions for creating a protein known as ” ZASP” can cause the newly defined disorder. The genes involved in zaspopathy are passed along to offspring in a dominant manner. This means that a child will develop the disorder by inheriting one copy of the mutant gene from one parent. The Mayo Clinic researchers tentatively named the new syndrome “zaspopathy” after the affected ZASP protein.

Significance of the Mayo Clinic Research

The identification of this new form of muscular dystrophy highlights the importance of scientific collaborations and the integration of different kinds of data. Laboratory information from ZASP alone was not enough to clarify the finding; clinical data from a large patient base was also necessary to support the clues given by ZASP. “The fact that we could pull together all different types of data and that it all pointed to the ZASP protein was key to the success of this effort,” says Duygu Selcen, M.D., the Mayo Clinic neurologist who led the study.

Mayo Clinic is uniquely suited to efficiently access and integrate data because the patient care mission of Mayo Clinic provides researchers so much access to many forms of medical information, according to Dr. Selcen. These forms of information include clinical observation of patients, analysis of diseased and healthy tissue samples, as well as genetic and molecular investigations.

The discovery of zaspopathy is also important because it supports the “candidate gene” approach for finding mutations that can cause human disease. “In this approach, we select specific genes to examine based on a detailed knowledge of how a disease affects a particular part of the body,” says Andrew Engel, M.D., a Mayo Clinic neurologist who worked on the project. Dr. Engel explains that the results with zaspopathy show the usefulness of the candidate gene in speeding up and simplifying the search for therapies and cures.

About Muscular Dystrophy

Muscular dystrophy is a group of rare inherited muscle diseases in which muscle fibers are unusually susceptible to damage. The different forms of the disease are distinctive in the inheritance pattern, primary muscles and genes affected, and prognosis, according to the National Institute of Neurological Disorders and Stroke .

Disability caused by muscular dystrophy falls on a continuum from mild weakness and loss of strength to premature death, usually in the 20s. In most forms of muscular dystrophy, it is primarily the muscles that control movement that become progressively weaker. However, in some types of muscular dystrophy, heart and other involuntary muscles and other organs are also affected. While there is no cure, various therapies, medications or orthopedic surgeries can slow the course of most forms.