What is a genetic variant or mutation?

A genetic variant (sometimes called a mutation) is a change in the DNA (the genetic code that gives the body its instructions). Some changes disrupt how a gene works and cause disease; others have no effect. In LAMA2-RD, the gene mutations in the LAMA2 gene mean the body cannot produce enough functioning laminin alpha-2 protein (also called merosin) which normally provides stability to muscles.