{"h1":"What is Rett Syndrome?","faq":[{"a":"No. They can look similar during the regression phase because both can affect communication and behaviour, but Rett syndrome is a distinct genetic condition (mostly caused by MECP2 changes) with its own pattern of loss of hand use and repetitive midline hand movements. A clinical and genetic evaluation tells them apart.","q":"Is Rett syndrome the same as autism?"},{"a":"It is seen almost entirely in girls. It can occur in boys but is extremely rare and usually presents differently. A clinician and genetic team confirm the picture in each child.","q":"Does Rett syndrome only affect girls?"},{"a":"No. Rett syndrome is caused by a genetic change, in most cases occurring spontaneously. Nothing in your parenting, feeding or care causes it. Your role now is to support your child with the right medical and therapy team.","q":"Did anything I do as a parent cause Rett syndrome?"},{"a":"Yes. While the condition itself is identified and managed medically, therapy is vital and lifelong — supporting communication, hand function, movement and daily-living skills, and protecting your child's engagement and quality of life.","q":"Can therapy help my child with Rett syndrome?"}],"lang":"en","slug":"what-is-rett-syndrome","title":"What is Rett Syndrome?","entity":{"key":"rett","kind":"condition","name":"Rett Syndrome","slug":"rett-syndrome"},"lenses":[{"kind":"stakeholder","label":"Parent","value":"parent"},{"kind":"domain","label":"Context","value":"context"},{"kind":"intent","label":"Definition","value":"definition"},{"kind":"lifecycle","label":"Screen","value":"screen"},{"kind":"route","label":"Special-Education","value":"special-education"},{"kind":"empowerment","label":"Early Clarity","value":"early_clarity"}],"parent":{"key":"conditions","label":"Conditions"},"related":[{"lang":"en","slug":"what-is-rett-syndrome-and-what-are-its-icd-11-features-in-early-childhood","title":"What is Rett Syndrome, and its ICD-11 features in early childhood?"},{"lang":"en","slug":"how-common-is-rett-syndrome-in-children","title":"How Common Is Rett Syndrome in Children?"},{"lang":"en","slug":"when-should-i-worry-that-my-2-year-old-might-have-rett-syndrome","title":"When should I worry that my 2-year-old might have Rett Syndrome?"},{"lang":"en","slug":"what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood","title":"What is Rett Syndrome, and what does it look like in early childhood?"},{"lang":"en","slug":"how-is-rett-syndrome-diagnosed-in-a-child","title":"How is Rett Syndrome diagnosed in a child?"},{"lang":"en","slug":"what-are-the-early-signs-of-rett-syndrome","title":"Early Signs of Rett Syndrome"}],"summary":"Rett syndrome (ICD-11 LD90.0) is a rare neurodevelopmental condition, almost always in girls, caused mostly by MECP2 gene changes. After typical early development, a child shows slowing head growth, loss of purposeful hand use and spoken words, and repetitive midline hand movements. It needs prompt medical and genetic referral, with therapy supporting communication, movement and daily function lifelong.","answer_md":"*A baby who begins as expected, then quietly loses skills already learned — that pause-and-regression pattern is what Rett syndrome describes.*\n\n## In short\nRett syndrome (ICD-11 **LD90.0**) is a rare, genetically-driven neurodevelopmental condition seen almost entirely in girls. After an apparently typical first 6–18 months, a child shows a distinctive slowing and then a loss of purposeful hand use and spoken words, alongside the emergence of repetitive hand movements (such as wringing, washing or mouthing). It is caused in most cases by changes in the *MECP2* gene — so it is a medical-genetic condition, identified by a clinician, not something parenting causes.\n\n## What this looks like in early childhood\nThe classic story is one of **regression after an early period of typical development**. Parents often notice: slowing of head growth, loss of previously-acquired hand skills, loss of babble or first words, and the appearance of constant midline hand movements that replace useful reaching and grasping. Walking may become unsteady or be lost, and some children show breathing irregularities, teeth-grinding or periods of unsettled mood. Because it can be confused with autism in the regression phase, a careful clinical and genetic evaluation is what distinguishes it.\n\nRett syndrome is recognised through a **clinical genetics and neurology pathway** — the priority when regression is suspected is prompt medical and genetic referral, not therapy alone. Therapy then plays a vital, lifelong role in protecting communication, movement, hand function and quality of life.\n\n## The Pinnacle way\nThis is general information, not a diagnosis — a clinical [AbilityScore®](/ask/what-is-the-abilityscore-and-how-is-it-calculated), a clinician-administered structured assessment, and any diagnosis are formed only at a Pinnacle Blooms Network centre under qualified clinician care, alongside the medical and genetic team. For children with confirmed [Rett syndrome](/rett-syndrome), our therapists build individualised support spanning communication, motor and daily-living goals, including [occupational therapy](https://www.pinnacleblooms.org/best-occupational-therapy-center-india-proven-improvement-rate) to protect hand function and engagement.\n\n## Trusted sources\nWHO ICD-11 (neurodevelopmental disorders, code LD90.0); paediatric guidance from the American Academy of Pediatrics and HealthyChildren.org on developmental regression and when to seek review.\n\n**Next step —** If your child has lost hand skills or words they once had, book a developmental review now so we can route you promptly to combined medical, genetic and therapy care.","canonical":"https://pinnacleblooms.org/ask/what-is-rett-syndrome","editorial":{"reviewed_at":"2026-06-11T20:12:18.613642+00:00","reviewed_by":null,"developed_by":"SETU Consortium · Pinnacle Blooms Network"},"alternates":[{"href":"https://pinnacleblooms.org/ask/what-is-rett-syndrome","lang":"en","indexable":true},{"href":"https://pinnacleblooms.org/ask/what-is-rett-syndrome-te","lang":"te","indexable":true}],"dimensions":[{"key":"conditions","label":"Conditions"}],"meta_title":"Rett Syndrome: A Simple, Caring Definition","meta_robots":"index, follow, max-image-preview:large","everyday_tip":"Keep a simple month-by-month note or short videos of your child's hand use and words. If a skill they clearly had starts to fade, share these with your clinician — regression after typical development is the key signal to act on.","published_at":"2026-06-10T10:58:00.048774+00:00","reading_paths":[{"key":"understand","items":[{"lang":"en","slug":"what-is-rett-syndrome-and-what-does-it-look-like-in-early-childhood","title":"What is Rett Syndrome, and what does it look like in early childhood?","reason":"Linked from this answer"},{"lang":"en","slug":"what-is-rett-syndrome-and-what-are-its-icd-11-features-in-early-childhood","title":"What is Rett Syndrome, and its ICD-11 features in early childhood?","reason":"Linked from this answer"},{"lang":"en","slug":"how-does-rett-syndrome-affect-a-child-s-daily-life","title":"How Rett Syndrome Affects a Child's Daily Life","reason":"Same topic"},{"lang":"en","slug":"is-rett-syndrome-considered-a-disability","title":"Is Rett Syndrome considered a disability?","reason":"Same 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