Xia-Gibbs Syndrome (XGS) is a rare genetic condition caused by a change (or mutation) in the AHDC1 gene. This gene helps regulate important functions in early brain development, and when it doesn’t work as expected, it can lead to a range of developmental challenges.

XGS affects each person differently. It is not a condition with a “set path” or guaranteed list of outcomes. Some individuals may have mild learning and speech delays, while others might require long-term, full-time support with communication, mobility, and daily living.

Because of its rarity, many doctors — including specialists — may not have encountered this syndrome before. That can feel frustrating, but it also means you’re not at fault for not having answers right away. Diagnosis is just the beginning — and we’re here to help you find your way through it.

The effects of Xia-Gibbs Syndrome vary widely. Some of the more commonly observed characteristics include:

• Delayed milestones, such as sitting, crawling, or walking later than expected

• Low muscle tone (hypotonia), making movements feel floppy or uncoordinated

• Speech and language difficulties, ranging from mild delays to limited verbal communication

• Sleep issues, including frequent waking or obstructive sleep apnoea

• Seizures, although not all children experience them

• Feeding difficulties, particularly in infancy

• Learning disabilities, which may range from mild to profound

Some children are able to walk, talk, and attend school with support. Others may communicate using signs or pictures, or rely more heavily on equipment or adapted routines. It’s impossible to predict everything from the outset — and that can be one of the hardest parts. But progress is possible, and support systems do exist.

Every child with XGS deserves to be seen as more than their diagnosis — as a whole person with potential, individuality, and the ability to thrive with the right help in place.

Xia-Gibbs Syndrome is classified as an ultra-rare disorder, with fewer than 500 known cases worldwide. It was first identified in 2014 by Dr. Xia and Dr. Gibbs — hence the name.

Because it is so rare, families often have to become advocates, educators, and navigators all at once. That can feel like a heavy load — but you don’t have to carry it alone. We are building a community, both in the UK and with international partners, so that no family has to feel isolated after receiving this diagnosis.

Yes — although it may look different from what you had planned.

Living with Xia-Gibbs Syndrome can come with challenges, but it also opens the door to unexpected strengths, milestones, and moments of joy. Many families say that their child with XGS has taught them resilience, patience, humour, and a new way to experience life.

With consistent support — from family, educators, therapists, and peers — children with XGS can achieve things once thought impossible. They can form strong relationships, engage with the world around them, and live lives filled with purpose and connection.

There is no single version of a “good life.” Your child’s path may be unique, but it can still be beautiful.

What Should I Do Next?

You don’t need to have all the answers now — but here are some early steps that can help:

Reach out to us. We can connect you with other UK families, provide guidance, and answer your questions at your pace.

Build your support team. Ask your GP or paediatrician for referrals to:

• A community paediatrician who can monitor development and coordinate support

• Speech and language therapists (SLT) for communication development

• Occupational therapists (OT) to support fine motor skills, feeding, and daily routines

• Physiotherapists for muscle strength, movement, and walking

• Sleep clinics if sleep is a concern

Learn about available support:

• An Education, Health and Care Plan (EHCP)

• Disability Living Allowance (DLA)

• Early Help support via your local council

IMPORTANT: If your child has recently received a diagnosis of Xia-Gibbs Syndrome, we strongly encourage you to register with the global XGS patient registry. This registry plays a vital role in helping medical teams, researchers, and clinicians better understand the condition and its many variations.

Although our UK charity is here to support you locally, the official registry is managed by our trusted partners at the Xia-Gibbs Society in the United States. When you register, they will share your details (with your consent) with the research team led by Professor Gibbs, who continues to study this rare condition.

Register here:
It’s free, secure, and essential for advancing future research.

We also support clinicians, therapists, and specialists who want to better understand Xia-Gibbs Syndrome. This includes case summaries, diagnostic guidance, and current research.

If you're working with a patient who has recently received this diagnosis, we encourage you to explore our dedicated clinician page.

Click here for more information