Rett’s Syndrome
It was first described by Austrian paediatrician Andreas Rett in 1966.
Huda Zoghbi demonstrated in 1999 that Rett syndrome is caused by
mutations in the gene MECP2.
Rett syndrome, originally termed as cerebroatrophic
Genetic
Characteristics hyperammonemia, is a neurodevelopmental disorder of the grey matter
of the brain that almost exclusively affects females but has also been
found in male patients. The clinical features include small hands and feet
and a deceleration of the rate of head growth. Repetitive stereotyped hand
movements, such as wringing and/or repeatedly putting hands into the
mouth, are also noted. People with Rett syndrome are prone to
gastrointestinal disorders and up to 80% have seizures. They typically
have no verbal skills, and about 50% of individuals affected do not walk.
Scoliosis, growth failure, and constipation are very common and can be
problematic.
Rett syndrome is one of the original DSM-IV designated PDDs and the
only one for which a specific genetic etiology has been identified.
Discovered by
Prevalence
The incidence of Rett Syndrome is estimated at 1 in 10,000 females; in
the United States approximately 16,000 children and women affected.
Prevalence of
ASD in
Tuberous
Sclerosis
Studies show figures of 1% of individuals with autism have a diagnosis
of Rett Syndrome.
According to Miles (2011) 17% of girls with confirmed Rett Syndrome
had been given an earlier diagnosis of Autism. An analysis of these girls’
background history revealed milder, later developing Rett syndrome
symptoms and they were able to retain more functional hand use.
Causes
Mutations in a gene called MECP2 (methyl-CpG-binding protein 2) were
identified as the cause of Rett Syndrome in 1999, in the laboratory of
Huda Zoghbi, M.D. at Baylor College of Medicine. First discovered by
Adrian Bird, Ph.D., in 1990, MECP2 produces a multi-functional protein,
also called MeCP2, which regulates the activity of a host of other genes
crucial to normal development.
With rare exceptions, Rett Syndrome is sporadic, rather than an inherited
disorder that is passed on from one generation to the next. In most cases,
the damaged copy of MECP2 can be traced to the paternal allele, the
result of a random sperm mutation. The incidence of recurrence in a
family is less than 1%
Regional Autism Team. Differential Diagnosis information. August 2013.
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Diagnosis
The diagnosis of Rett Sydrome is based upon clinical criteria, the
identification of MECP2 has made DNA testing and confirmation
possible for affected individuals and their families. To date,
approximately 95% of girls exhibiting Rett symptoms have one of the
over 200 currently identified MECP2 mutations.
Physical Features

Jerky, stiff gait.

Uncoordinated breathing

Seizures

Motor disorders
Cognitive and Behavioural Features
Shared
features with
ASD.
Treatment

Significant cognitive impairment

Stereotyped hand movements
Signs of Rett syndrome that are similar to autism:

screaming fits

inconsolable crying

breath holding, hyperventilation & air swallowing

lack of social/emotional reciprocity

Language development regression around 5 to 18 months of age.

Sometimes may even stop talking at three years of age.

Retain prelinguistic communication skills

Social anxiety

Withdrawal and disinterest in other people

Reduced imitation skills

sensory problems

Stereotyped hand movements
Although there is no cure for Rett syndrome there are a number of
Regional Autism Team. Differential Diagnosis information. August 2013.
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interventions that greatly improve an individual’s ability to function and
communicate in their everyday lives. It is suggested that intervention
should focus on developing further the joint attention behaviors,
intentional communications and communicative functions spontaneously
used by individuals with disorders in the Rett syndrome complex.
Two intervention studies by Sigafoos and his colleagues (i.e., Sigafoos et
al. 1995, 1996) in a case series showed that children with Rett syndrome
may be taught to express choices via eye gazing and reaching and
requesting via a “want” symbol. Results of these studies suggest that
children with Rett syndrome may display intentional alternative
communicative behaviors and that such behaviors may be taught using
instructional procedures
More
information


Rett syndrome Ireland
National Institute of Neurological disorders and stroke
http://www.ninds.nih.gov/disorders/rett syndrome.
Physical features and natural history:
The course of Rett syndrome, including the age of onset and the severity of
symptoms, varies from child to child. Before the symptoms begin, however, the child
generally appears to grow and develop normally, although there are often subtle
abnormalities even in early infancy, such as loss of muscle tone (hypotonia), difficulty
feeding, and jerkiness in limb movements. Then, gradually, mental and physical
symptoms appear. As the syndrome progresses, the child loses purposeful use of her
hands and the ability to speak. Other early symptoms may include problems crawling
or walking and diminished eye contact. The loss of functional use of the hands is
followed by compulsive hand movements such as wringing and washing. The onset of
this period of regression is sometimes sudden.
Useful Research Papers
Miles, J.H. (2011). Autism Spectrum Disorders- A genetics review. Genetics in
Medicine. 13(4)279-290.
Sigafoos J, Laurie S, Pennell D. Preliminary assessment of choice making among
children with Rett syndrome. Journal of the Association for Persons with Severe
Handicaps. 1995;20:175–184.
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