Many families spend a long time worried and unsure when their little girl, who seemed to be developing well, starts to lose skills somewhere between 6 and 18 months. Sometimes this is first called autism or another condition, when it is actually Rett syndrome.
What is Rett syndrome?
Rett syndrome is a rare genetic condition that affects how the brain develops. It mostly affects girls. In most cases it is caused by a change in a gene called MECP2, and this change usually happens for the first time in the child rather than being inherited from the parents.
How it differs from autism
| What we look at | Rett syndrome | Autism |
|---|---|---|
| Early development | Seems typical at first, then skills are lost between about 6 and 18 months. | Differences in communication usually show gradually, without a sudden loss of hand skills. |
| Hands | Purposeful hand use is lost and replaced by repeated wringing, clapping or mouthing. | Hand flapping may happen, but children keep using their hands to hold and play. |
| Eye contact | Often warm, strong eye contact; girls may “talk with their eyes”. | Eye contact and back-and-forth social interaction are often harder. |
| Head growth | Head growth often slows after birth. | Head size is usually typical. |
| Breathing and joints | Breath-holding or fast breathing while awake; stiff joints and a curving spine can develop. | Breathing and the skeleton are not usually affected. |
Why the genetic test matters
A simple blood test for the MECP2 gene confirms the diagnosis. Knowing the real cause means your daughter gets the right support from the start, such as:
- Eye-gaze communication tools that let her make choices and express herself with her eyes.
- Monitoring of breathing and heart rhythm, which can be affected in Rett syndrome.
- Physiotherapy and movement programmes to keep joints flexible and help her stand and walk for as long as possible.
You are not alone: If your daughter has lost words or hand skills after developing well, book an assessment. A clear diagnosis is the first step to the right care plan.