Rett syndrome


Rett syndrome is a condition that affects the nervous system, causing problems with learning and development. It affects girls almost exclusively. Although the syndrome is present from birth, symptoms and signs most commonly appear during the second year. People with Rett syndrome are almost always totally dependent on others for their needs throughout their lives, but severity may vary considerably.


Last updated August 2016 by Dr H Cass, Neurodisability Consultant, Evelina Children’s Hospital, London, UK.

Although great care has been taken in the compilation and preparation of all entries to ensure accuracy, we cannot accept responsibility for any errors or omissions. Any medical information is provided is for education/information purposes and is not designed to replace medical advice by a qualified medical professional.

What are the symptoms?

Babies with Rett syndrome are usually placid and inactive with slow learning. Within a few months of birth, the child’s head size may fail to increase at the normal rate indicating that the brain is not growing.

Between 1-3 years:

  • the abnormal hand movements which are characteristic of the condition appear, such as complex finger movements, with twisting and squeezing of the hands
  • this is usually associated with loss of hand skills, speech, and early motor skills
  • the child may be agitated and distressed and breathing may become irregular
  • there may be short non-epileptic ‘vacant’ spells.

The early agitation usually settles after a year or two.

Later development:

  • affected children usually have problems with poorly regulated muscle tension. Some girls do not achieve walking, and those that do walk tend to have a broad-based gait.
  • there is a tendency to develop scoliosis
  • other problems include feeding difficulties, periodic agitation and breathing problems
  • most girls are non-verbal
  • epilepsy may occur, usually between 5-10 years.

Despite these symptoms, many individuals with Rett syndrome continue to live well into middle age and beyond. They enjoy social contact, and seem to be particularly responsive to music.

What are the causes?

A mutation on MECP2, a gene at the tip of the X chromosome, is the cause of the condition in the majority of people affected. There are other less common genetic conditions which result in a similar clinical picture including CDKL5, another gene on the X chromosome, associated with more severe and early onset epilepsy and FOXG1 syndrome.

How is it diagnosed?

Doctors will suspect Rett syndrome by observing typical signs during a child’s early development. Brain scans may confirm poor growth of the brain. The diagnosis is confirmed by carrying out a molecular test (testing the DNA to look for a mutation) in the MECP2 gene or rarely CDKL5 or FOXG1. However, if the clinical signs are present a child may still receive a diagnosis of Rett syndrome, even with negative genetic findings.

How is it treated?

Treatment focuses on management of the symptoms. Medication may be needed to improve breathing irregularities and help with movement difficulties, and anticonvulsants can be used to control seizures. There should be regular monitoring for scoliosis. Possible heart conduction abnormalities should be evaluated with an electrocardiogram (ECG).

Physiotherapy can improve mobility. A brace may help with scoliosis and hand splints can be used to help improve hand function. In those who are not mobile, good adaptive seating is essential. Special nutrition can improve weight gain and the growth of a child. Some children will go on to need a gastrostomy (surgical opening through the abdomen into the stomach) for feeding.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
Most cases are due to sporadic mutation (occurring by chance). In these cases, the risk of another child being affected is very low. Families should seek advice from their regional genetics centre.

Prenatal diagnosis
Prenatal diagnosis is possible where the mutation has been identified in an individual family. The possibility of prenatal diagnosis is best investigated in advance of a pregnancy. Advice may be obtained from a regional genetics centre.

Is there support?

Rett UK

Helpline: 01582 798 911

The Organisation is a Registered Charity in England and Wales No. 1137820 and in Scotland No. SCO47369. It provides information and support for families affected by Rett syndrome. The Organisation has a network of local support groups and offers regional roadshow events.

Group details last updated May 2019.

Reverse Rett

Tel: 0161 434 8117

Reverse Rett is a Registered Charity in England and Wales No. 1136809. It provides information and support on Rett syndrome and related MECP2 disorders, and runs a private Facebook forum for families. The Charity is also actively involved in fundraising for research initiatives, and also offers a parent mentoring and linking scheme.

Group details confirmed August 2016.

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