Question: What are the genetic changes related to collagen VI-related myopathy ?
Answer: Mutations in the COL6A1, COL6A2, and COL6A3 genes can cause the various forms of collagen VI-related myopathy. These genes each provide instructions for making one component of a protein called type VI collagen. Type VI collagen makes up part of the extracellular matrix that surrounds muscle cells and connective tissue. This matrix is an intricate lattice that forms in the space between cells and provides structural support. The extracellular matrix is necessary for cell stability and growth. Research suggests that type VI collagen helps secure and organize the extracellular matrix by linking the matrix to the cells it surrounds. Mutations in the COL6A1, COL6A2, and COL6A3 genes result in a decrease or lack of type VI collagen or the production of abnormal type VI collagen. While it is difficult to predict which type of mutation will lead to which form of collagen VI-related myopathy, in general, lower amounts of type VI collagen lead to more severe signs and symptoms that begin earlier in life. Changes in type VI collagen structure or production lead to an unstable extracellular matrix that is no longer attached to cells. As a result, the stability of the surrounding muscle cells and connective tissue progressively declines, which leads to the muscle weakness, contractures, and other signs and symptoms of collagen VI-related myopathy.
Source: GHR