Rett syndrome (RTT), Causes and Treatment

Rett syndrome (RTT) is a rare genetic condition that results in certain mental and physical disabilities. It tends to only affect females.

RTT develops due to a mutation in one of the genes on the X chromosome. The gene in question is the methyl CpG binding protein 2 (MECP2) gene.

RTT is very rare and occurs in around 1 in every 10,000–15,000 live female births. There are four stages of RTT, and the first stage typically begins between the ages of 6 and 18 months.

RTT is a neurological condition. An infant with RTT will usually have normal early growth at the beginning of life, followed by a number of symptoms that develop in stages.

Infants with RTT may have one or more of these common symptoms:

• slowing of development
• loss of purposeful use of the hands
• distinctive hand movements
• slowed brain growth
• slowed head growth
• difficulty walking
• seizures
• intellectual disability

The condition primarily affects females. This is because the MECP2 gene is on the X chromosome. Females have two X chromosomes, while males only have one X chromosome. In females, one of each two X chromosomes is inactive in each cell.

Which one is active is random, which is why the severity of RTT varies so much from person to person.

In males, there is only one X chromosome, so RTT is typically lethal to the male fetus. If the fetus does survive to birth, the infant will likely have a severe case of RTT and likely die early in life.

Causes

RTT is almost always due to a mutation in the MECP2 gene. This gene is located on the X chromosome. Scientists discovered this gene in 1999, and they believe its role is to control the functions of many other genes.

Mutations in the CDKL5 and FOXG1 genes can also cause RTT, but there will be slightly different clinical patterns when this is the case.

According to one study, despite the scientific progress that researchers have made since the discovery of RTT, the exact way in which these mutations cause RTT is largely unknown.

Treatments

There is currently no cure for RTT, and the reason behind the mutations that cause it is still largely unknown.

For this reason, treatment options for RTT are limited. Most treatment focuses on symptom relief.

Treatment options that can help a person with RTT include:

• Medications: Medications can help treat breathing irregularities and motor difficulties. A doctor may also prescribe drugs to help control seizures.
• Physical therapy and hydrotherapy: This can help a person with their mobility issues and balance.
• Occupational therapy: Occupational therapy can help a person develop the skills they need to perform tasks such as dressing and feeding.
• Speech and language therapy: This can help a person learn how to use nonverbal communication and improve their social interaction.
• Braces: These may be helpful for correcting the effects of scoliosis.
• Splints: A doctor may use splints to help adjust hand movements.
• Nutritional help: Supplements can strengthen the bones and assist with scoliosis. Having a specific nutritional program may help the person maintain a moderate weight.