X-linked dominant inheritance

X-linked dominant is a description of an autosomal dominant inherited genetic disorder caused by mutations in genes on the X chromosome. This inheritance pattern is less common than X-linked recessive disorders. Females are more frequently affected than males, and the chance of passing on an X-linked dominant disorder differs between men and women.

Inheritance

Females usually have two X chromosomes, while most males have one X and one Y chromosome. If a child has inherited the mutation from the X chromosome of one of their parents they will have the condition. A woman with an X-linked dominant disorder has a 50% chance of having an affected daughter or son with each pregnancy. The sons of a man with an X-linked dominant disorder will not be affected, but his daughters will all inherit the condition.

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  A woman with an X-linked dominant disorder has a 50% chance of having an affected child.
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  The daughters of a man with an X-linked dominant disorder will all inherit the condition.

Some X-linked dominant conditions such as Aicardi Syndrome are fatal to boys, therefore only girls with these conditions survive. Similarly, individuals with Klinefelter's Syndrome are referred to as "47,XXY Males".

See also

• Hypophosphatemia
• Retinitis pigmentosa
• Rett syndrome
• Sex linkage