AHDC1 (Xia-Gibbs syndrome)
Below is a summary for the AHDC1 gene observed in research publications. This is not meant to take the place of medical advice. Click HERE for the full gene guide, which includes more information, such as the chance of having another child with this condition, or specialists to consider for people with this condition.
What is AHDC1-related syndrome or Xia-Gibbs syndrome?
Xia-Gibbs syndrome happens when there are changes to the AHDC1 gene. These changes can keep the gene from working as it should.
The AHDC1 gene plays a key role in the growth of the brain.
Because the AHDC1 gene is important in the development and function of brain cells, many people who have Xia-Gibbs syndrome have:
- Developmental delay
- Speech delay
- Sleep apnea, a disorder in which breathing stops and starts
Do people who have Xia-Gibbs syndrome look different?
People who have Xia-Gibbs syndrome can look different. Appearance can vary and can include some but not all of these features:
- Broad forehead
- Widely spaced eyes
- Flat bridge of nose
- Thin upper lip
How many people have AHDC1- related syndrome?
As of 2019, doctors had found about 60 people in the world with changes in the AHDC1 gene. The first case of AHDC1-related syndrome was described in 2014. Scientists expect to find more people who have the syndrome as access to genetic testing improves.
- 40% are nonverbal (all male)
- 20% use less than 50 words
- 10% use more than 50 words but do not speak in full sentences
- 30% use complete sentences and more than 200 words
People often have some level of intellectual disability.
About one-half of those who have the syndrome have sleep apnea, a condition in which people stop breathing during sleep for short periods of time. Some use a breathing aid during sleep. One-quarter have autism or symptoms of autism.
Many children who have the syndrome grow slowly and are shorter than their peers.
Research Article Summaries