Muscular Dystrophy Award funded by Colin Gordon Munro Estate
Muscular dystrophy and protection against heart disease.
Professor Richard Jackson
School of Medicine, Griffith University and Department of Medicine, Logan Hospital & University of Queensland
Myotonic dystrophy type 1 is a genetic disease, which is the commonest muscular dystrophy to affect both adults and children. It affects about 1 in 8000 people worldwide, and the so-called classical form of the disease shows clinical manifestations by the teenage years or early 20s. Myotonic dystrophy affects skeletal, smooth and cardiac muscle, and begins by affecting the hands, feet and facial muscles, and progresses over time to affect all skeletal muscle groups. The major causes of disability and death are effects on the heart and the lungs, causing abnormal heart rhythms, poor contraction of the heart muscle and, in the lungs, an increased tendency to sleep apnea, aspiration pneumonia and poor respiratory effort. As well as these problems, these patients have a modified form of the “metabolic syndrome”: they develop high blood fats, impaired ability to metabolise glucose and, subsequently, develop frank type 2 diabetes, and deposit excess fat inside the abdomen. These are all powerful “risk factors” for coronary heart disease, and most people who develop these problems are prone to early heart attacks and angina. Myotonic patients do not develop early coronary disease. My research will try to find out why myotonic patients are relatively protected against this very common problem of coronary disease, even though they have classical risk factors. We will do this by comparing the activity of certain genes known to associated with coronary disease in myotonic patients and in other people who have the metabolic abnormalities described above, but do not have myotonic dystrophy. This may inform us of ways to protect against the commonest killer in the general community, coronary heart disease.