What are the genetic changes related to inclusion body myopathy 2 ?
Mutations in the GNE gene cause inclusion body myopathy 2. The GNE gene provides instructions for making an enzyme found in cells and tissues throughout the body. This enzyme is involved in a chemical pathway that produces sialic acid, which is a simple sugar that attaches to the ends of more complex molecules on the surface of cells. By modifying these molecules, sialic acid influences a wide variety of cellular functions including cell movement (migration), attaching cells to one another (adhesion), signaling between cells, and inflammation.  The mutations responsible for inclusion body myopathy 2 reduce the activity of the enzyme produced from the GNE gene, which decreases the production of sialic acid. As a result, less of this simple sugar is available to attach to cell surface molecules. Researchers are working to determine how a shortage of sialic acid leads to progressive muscle weakness in people with inclusion body myopathy 2. Sialic acid is important for the normal function of many different cells and tissues, so it is unclear why the signs and symptoms of this disorder appear to be limited to the skeletal muscles.