P.O. Box 50030 London, ON N6A 6H8 info@rett.ca (519) 474-6877

Rett Syndrome

  • Neurological disorder affecting 1 in 10,000 to 1 in 23,000 females, caused by the MECP2 gene on the X chromosome
  • Normal development until 6 to 18 months, followed by a period of regression that leads to a loss of speech, motor and hand skills and physical disabilities
  • Development of repetitive hand movements
  • Possible EEG abnormalities, irregular breathing, seizures, scoliosis, teeth grinding, chewing and /or swallowing difficulties, poor weight gain, abnormal sleeping patterns and small feet
  • Apraxia (dyspraxia), the inability to program the body to perform motor movements, the most severely handicapping aspect of Rett Sydrome
  • Attractive features and penetrating eyes


  • Approximately 85% of all patients clinically diagnosed with RTT also test positive for a MECP2 mutation.
  • Diagnosis must first be confirmed using the diagnostic criteria
  • 99.5% of cases of RTT occur only once in a family


Intensive physical, occupational, speech and augmentative communication therapies are highly recommended in supporting a female with RTT.

Despite their difficulties, girls and women with RTT can continue to learn and enjoy family and friends well into middle age and beyond.  They experience a full range of emotions and show their engaging personalities as they take part in social, educational and recreational activities at home and in the community.

Diagnostic Criteria

  • Period of apparent normal development until 6 – 18 months
  • Normal head circumference at birth followed by slowing of the rate of head growth
  • Loss of verbal language and emerging social withdrawal
  • Purposeful hand use is replaced by stereotypical hand movements such as hand wringing/squeezing, clapping/tapping, mouthing
  • If able to walk the gait is usually wide-based and stiff legged
  • Shakiness of torso and/or limbs, especially when upset

Supportive Criteria

  • Breathing pattern irregularities which include hyperventilation, breath holding, apnea, air swallowing
  • EEG abnormalities
  • Seizures
  • Scoliosis
  • Teeth grinding
  • Gastrointestinal issues which may include reflux, constipation, poor nutrient absorption
  • Growth retardation and decreased body fat and muscle mass
  • Biting/chewing/swallowing difficulties
  • Poor circulation to legs and feet
  • Decreased mobility with age
  • Muscle rigidity/spasticity/joint contractures
  • Small feet
  • Abnormal Sleep patterns
  • Irritability and agitation