Duchenne is a condition primarily affecting boys, being described as an X-linked recessive condition. X-linked recessive conditions describe alterations in a specific gene, causing the condition in males but not in females. Duchenne results from the alteration of the dystrophin gene located on the X-chromosome.

Alterations of the dystrophin gene on the X-chromosome are inherited from the mother, who is described as being a carrier of the dystrophin gene. Carriers of the Duchenne gene will not suffer from the condition themselves as they have two X chromosomes. In some cases random spontaneous alterations can occur causing Duchenne, these are not inherited from the mother.

In females the unaffected X chromosome can compensate for the mutated chromosome, with less that 1% of those with Duchenne being female.

Males only have one X and one Y chromosome; therefore males who inherit a mutated Duchenne gene on the X chromosome will have the condition. Males with the condition cannot pass the disorder onto their male offspring as males pass on their Y chromosome. Daughters who inherit an altered X-chromosome will be carriers and can pass on the altered dystrophin gene.

Duchenne occurs across all races and cultures and can affect those with the condition in different ways, no one individual with Duchenne is the same.

Find out more in Genetics explained - Genetics and Duchenne.

Figure 1 - Inheritance pattern in Duchenne muscular dystrophy (DMD). Duchenne is an X-linked condition mainly affecting boys with girls being carriers.