Duchenne muscular dystrophy in a 46 XY female

The most common muscular dystrophy, Duchenne muscular dystrophy (DMD), is an X-linked disorder that ordinarily has full clinical expression only in males. Reports of typical clinical features in females are rare but have occurred with a phenotypically identical autosomal recessive muscular dystrophy as well as in females with X-chromosome abnormalities such as the Turner syndrome. A girl with full expression of DMD due to a 46 XY karyotype is reported, and other clinical conditions in which expression of the DMD gene occurs in females are reviewed.