Families

What is SPEG-related disease?
SPEG-related disease is a rare inherited condition caused by changes in the SPEGgene. People with SPEGchanges most often have a type of muscle disease called centronuclear myopathy, which causes weak or floppy muscles beginning at birth or in early infancy. Many people with SPEGchanges also have heart problems, especially a weakened, enlarged heart (dilated cardiomyopathy). The severity varies: some babies have very weak muscles and breathing or feeding difficulties, while others have milder symptoms.

Why does this happen?
SPEGmakes a protein that helps muscle cells work properly. When SPEG does not work correctly, the muscles and heart do not develop or function normally.

Will my child’s symptoms be the same as others?
Not always. Some people have severe muscle weakness and early heart disease; others have milder muscle problems or later-onset symptoms. The exact change in the gene helps doctors predict the likely course, but there is still variability.