DMD is inherited in an X-linked recessive manner. This type of inheritance requires the presence of one copy of a pathogenic variant in the gene located on the X-chromosome for males to be affected. When the pathogenic variant is inherited from the unaffected carrier mother, the male child will have the genetic disease. There is a 50% chance that a baby will inherit the pathogenic variant from the mother; females who inherit the pathogenic variant will be carriers, males who inherit the pathogenic variant will be affected. In DMD, 2/3 of the cases are inherited pathogenic variants, the remaining 1/3 result from new pathogenic variants in the male and are not inherited. In BMD, 90% of mothers are carriers of a pathogenic variant.