Can males have Rett syndrome?

Rett syndrome is a rare genetic neurological and developmental disorder that affects the development of the brain by causing progressive loss of motor and language skills.

Rett syndrome almost exclusively affects females and is very rare in males. The syndrome is primarily caused by mutations in the MECP2 gene, which is located on the X chromosome and regulates the activity of many other genes.

Because males only have one X chromosome, a mutation in the MECP2 gene cannot be compensated for by a healthy gene copy. As a result, they rarely survive infancy.

However, males with MECP2 mutations have been reported. These patients have more severe symptoms that appear earlier in life, with the disease manifesting itself at birth or shortly thereafter.

The majority of MECP2 changes in males are caused by spontaneous mutations that occur during the division and formation of sperm, the male germ cell.

Males who are affected may also have microcephaly. The disorder worsens over time, causing abnormal muscle tone, involuntary movements, severe seizures, and breathing irregularities.