Rett Syndrome by the Numbers
In each box, click the plus sign to learn more.
Prevalence and Statistics
1 in 10K-20K
Even rarer
No. of females worldwide
Occurence in males
Around 90%
6-18 months
4 stages
Cases due to MECP2 mutations
Age when symptoms usually begin
Phases of Rett syndrome
Symptoms and Related Conditions
Most children
Nearly all
60%-80%
Growth delays and feeding difficulties
Language impairment
Co-occurring epilepsy
Older children
Over 80%
Breathing irregularities
Scoliosis
Many children experience abnormal breathing patterns, such as breath-holding, hyperventilation, or air swallowing.
Most children with Rett syndrome have trouble gaining weight and growing at a typical rate. Feeding challenges, including chewing and swallowing difficulties, are common and may require support from nutrition or feeding specialists.
Rett syndrome is extremely rare in males, though we don’t have reliable statistics about just how rare it is. When this genetic disorder does occur in males, it’s often associated with more severe symptoms.
The majority of children with classic Rett syndrome have a mutation (change) in the MECP2 gene. This gene plays a key role in brain development and function.
Stage 1 Rett syndrome begins with subtle symptoms like delays in crawling and making less eye contact. During stage 2, between 1 and 4years of age, children rapidly lose skills they had. At stage 3, children hit a plateau in their developmental milestones and may start to experience seizures. In stage 4, usually after age 10, children usually experience reduced mobility and muscle weakness.
Rett syndrome is considered a rare disease. Most estimates suggest it occurs in roughly 5 to 10 out of every 100,000 females.
Scoliosis (atypical sideways curving of the spine) is common, especially as children grow older, largely due to decreased muscle tone.
Seizures are one of the most common medical conditions seen in Rett syndrome. While some people are able to control their seizures, others may experience frequent or difficult-to-treat epilepsy.
Most children with Rett syndrome appear to develop typically for the first several months of life. Symptoms often begin between 6 and 18 months, when developmental progress slows or skills like speech and purposeful hand use are lost.
Rett is known to cause differences in communication, which is why it’s commonly misdiagnosed as autism. While most children with Rett don’t use spoken language to communicate, many children find ways to communicate through eye gaze, facial expressions, or assistive technology.
[RETT-206] How Rare Is Rett Syndrome?
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Transcript
Rett Syndrome by the Numbers
In each box, click the plus sign to learn more.
Prevalence and Statistics
1 in 10K-20K
Even rarer
No. of females worldwide
Occurence in males
Around 90%
6-18 months
4 stages
Cases due to MECP2 mutations
Age when symptoms usually begin
Phases of Rett syndrome
Symptoms and Related Conditions
Most children
Nearly all
60%-80%
Growth delays and feeding difficulties
Language impairment
Co-occurring epilepsy
Older children
Over 80%
Breathing irregularities
Scoliosis
Many children experience abnormal breathing patterns, such as breath-holding, hyperventilation, or air swallowing.
Most children with Rett syndrome have trouble gaining weight and growing at a typical rate. Feeding challenges, including chewing and swallowing difficulties, are common and may require support from nutrition or feeding specialists.
Rett syndrome is extremely rare in males, though we don’t have reliable statistics about just how rare it is. When this genetic disorder does occur in males, it’s often associated with more severe symptoms.
The majority of children with classic Rett syndrome have a mutation (change) in the MECP2 gene. This gene plays a key role in brain development and function.
Stage 1 Rett syndrome begins with subtle symptoms like delays in crawling and making less eye contact. During stage 2, between 1 and 4years of age, children rapidly lose skills they had. At stage 3, children hit a plateau in their developmental milestones and may start to experience seizures. In stage 4, usually after age 10, children usually experience reduced mobility and muscle weakness.
Rett syndrome is considered a rare disease. Most estimates suggest it occurs in roughly 5 to 10 out of every 100,000 females.
Scoliosis (atypical sideways curving of the spine) is common, especially as children grow older, largely due to decreased muscle tone.
Seizures are one of the most common medical conditions seen in Rett syndrome. While some people are able to control their seizures, others may experience frequent or difficult-to-treat epilepsy.
Most children with Rett syndrome appear to develop typically for the first several months of life. Symptoms often begin between 6 and 18 months, when developmental progress slows or skills like speech and purposeful hand use are lost.
Rett is known to cause differences in communication, which is why it’s commonly misdiagnosed as autism. While most children with Rett don’t use spoken language to communicate, many children find ways to communicate through eye gaze, facial expressions, or assistive technology.