What is Rett Syndrome?
Rett syndrome is a rare neurological disorder affecting mainly females and very few males. It is present from conception and usually remains undetected until major regression occurs at around one year of age, when children may lose acquired skills and become withdrawn. Genetic but largely not inherited, Rett syndrome is usually caused by a fault on a gene called MECP2 which is found on the X chromosome. People with Rett syndrome have profound and multiple physical and communication disabilities and are totally reliant on others for support throughout their lives.
Rett syndrome was first described in 1966 by the Austrian doctor, Andreas Rett. It could occur in any family and affects approximately 1 in 12,000 girls born each year.
Almost all cases of Rett syndrome are caused by a mutation (change in the DNA) in the MECP2 gene, which is found on the X chromosome (one of the sex chromosomes). This gene contains instructions to make a particular protein (MeCP2) that is vital for brain development. The gene abnormality prevents nerve cells in the brain from working properly. Almost all people with Rett syndrome have no history of the disorder in their family, and the mutation has happened spontaneously.
Why is Rett syndrome almost always seen in girls?
Each person normally has one pair of sex chromosomes in each cell – females have two X chromosomes and males have one X and one Y.
Rett syndrome results when half the cells in the child’s brain and spinal cord are normal and half are abnormal (the child survives, but has a severe disability). This happens when the child has one X chromosome with the severe MECP2 abnormality and one X chromosome with the normal version of the gene. The child is almost always female as males don’t have a second X chromosome.
Rare exceptions of Rett syndrome in males occur when, for example, the male is born with an extra X chromosome so he has three sex chromosomes (XXY; known as Klinefelter’s syndrome), or when the change is found in only some of the boy’s cells (known as mosaicism).
Males who carry the abnormal MECP2 gene on their only X chromosome will usually develop a serious condition known as infantile encephalopathy and will not often survive beyond two years.
Males with less severe changes in their MECP2 gene can live a long life and are affected with learning difficulties but usually less severely than in Rett syndrome. Females who carry such (milder) changes on one of their two X chromosomes will often be perfectly healthy.
Children with Rett syndrome share common symptoms but it is a wide spectrum with some being less severely affected than others; each child is an individual and may not display every symptom but these are the most typical ones seen at various stages of the disorder. Symptoms can change over time and as children grow into adulthood different difficulties may present.
Stage 1: Early Signs and Slow Development
Babies with Rett syndrome appear to develop normally for the first year or eighteen months but may be quite floppy (hypotonia), have some difficulty feeding, show poor coordination of limbs and trunk and have unusual hand movements (wringing, clasping and mouthing).
A period of stagnation in development from about the end of the first year may last until regression occurs.
Stage Two: Regression
Regression may occur as early as nine months and as late as 30 months. In atypical cases this can occur later still. Skills in speech and purposeful hand movement are greatly reduced as repetitive and uncontrollable hand movements take over. Children may start to seem to withdraw socially which can lead to a mis-diagnosis of autism. There are often periods of distress, irritability and sometimes screaming for no obvious reason. If the child has started walking, their gait may become unsteady and posture stiff. Parents often remark on their children having a higher pain threshold than they have experienced with other children, particularly to external pain if accidentally hurt in some way. Head circumference which was normal at birth may now start slowing in growth.
Other problems that can develop during this stage are related to eating, chewing or swallowing as abnormal breathing patterns appear; breath holding, air swallowing, and hyperventilating. Bloating and constipation may be problematic often exacerbated by difficulties with fluid intake. Some children may also start to have epileptic seizures during this phase. There are many types of seizures and different ways that they can present from absences which may be momentary to grand mal or generalised tonic clonic seizures which can affect the whole body. An electroenchephalogram (EEG) is frequently used to determine the type of seizure, along with observations from parents and care givers and medication may be prescribed to help control the seizures.
Stage 3: Plateau
Can occur from as young as two years and up to 10 years of age; this stage can last for many years. There can be some improvement in some symptoms such as irritability and crying as well as showing more interest in their surroundings. However, weight gain can be difficult to achieve and breathing difficulties may worsen.
Stage 4: Deterioration in movement
Can last for years or even decades. The main symptoms at this stage are:
- the spine bending to the left or right side (scoliosis), although this often starts earlier and frequently worsens during puberty with each growth spurt
- spasticity (abnormal stiffness, especially in the legs)
- loss of the ability to walk
The repetitive hand movements may decrease by this stage and eye gaze usually improves. The seizures also usually become less of a problem in adolescence and early adult life, although they will normally be a lifelong problem that requires careful management and regular reviews with a neurologist.
Other features which are often seen include:
- EEG abnormalities
- Problems with sleeping marked by difficulty in falling asleep, waking for long periods (often with shrieking, laughter).
- Epilepsy – over 50% of people with Rett syndrome have some form of epileptic seizure at some time
- With age, muscles become increasingly rigid; joint deformities and muscle wasting may occur
- Development of scoliosis (curvature of the spine)
- Growth retardation
- Teeth grinding
Careful management of the symptoms with a care plan that involves physiotherapy, occupational therapy, speech and language therapy, hydrotherapy and music therapy can help the person with Rett syndrome live a full and happy life. Many people with Rett syndrome do live into late middle age, and in less severely affected people, into old age, but sadly some do die quite young. Complications caused by the disorder including pneumonia, epilepsy and heart rhythm abnormalities are the most common causes of premature death in people with Rett syndrome.
Rett UK is the only UK charity which provides professional support to people living with Rett syndrome across the UK.
Rett UK was founded in 1985 round a kitchen table by Yvonne Milne MBE. Since then they have grown to be the leading provider of information to not only families but also medical professionals new to the world of Rett syndrome.
Rett UK is a national charity dedicated to supporting and empowering people with Rett syndrome and their families.
Its strategic aims are to …
- provide professional family-support services, activities and events at a local, regional and national level
- educate health, social care and education professionals about Rett syndrome to enable quicker diagnosis and improved standards of care throughout the UK
- advocate for people with Rett syndrome to be given the support and resources needed to be active communicators
- promote, support and encourage research into new therapies and treatments for Rett syndrome
That everyone with Rett syndrome is given every possible opportunity to achieve their individual potential so that they may live their life to the full.
If you are a family looking for more information and support please email firstname.lastname@example.org.
Rett UK are a small team working on a national level. They receive NO government funding and rely entirely on donations and grants to fund our work.
If you would to support their fundraising efforts please email email@example.com