How is Duchenne muscular dystrophy inherited?
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In contrast, boys with the DMD gene do not have a second X chromosome and so they cannot compensate for the faulty gene. Therefore, boys with the DMD gene always have symptoms of the disease.

The DMD gene can be passed on from parent to child. For a woman who carries the DMD gene, there is a 1 in 2 chance that her sons will have DMD, and a 1 in 2 chance that her daughters will carry the gene.