Below is a summary for the AFF2 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 chance of having another child with this condition, or specialists to consider for people with this condition.

What is AFF2-related syndrome?

AFF2-related syndrome happens when there are changes to the AFF2 gene. These changes can keep the gene from working as it should. The AFF2 gene is also called FMR2 or FRAXE.

Key Role

The AFF2 gene plays a key role in brain development.


Because the AFF2 gene is important in the development and function of brain cells, many people who have AFF2-related syndrome have:

  • Intellectual disability
  • Developmental and speech delays
  • Autism or features of autism
  • Hyperactivity and attention difficulties
  • Behavior issues

Do people who have AFF2-related syndrome look different?

People who have AFF2-related syndrome typically do not look different from others.

How many people have AFF2-related syndrome?

Researchers estimate that about 1 in 25,000 to 1 in 100,000 newborn males have AFF2-related syndrome. There are likely many more undiagnosed people who have the syndrome. As of 2020, doctors had described about 46 people in the world with changes in the AFF2 gene. The first case of AFF2-related syndrome was described in 1993. Scientists expect to find more people who have the syndrome as access to genetic testing improves.


Many have language difficulties.


Most people have some degree of intellectual disability and
learning difficulties.


Many people have autism or show features of autism, such as social difficulties, excessive hand flapping, and restricted interests. Many also have attention difficulties, hyperactivity, and impulsivity.


Support Resources



GeneReviews are a great resource to bring to your child’s clinicians. These publications provide a summary of current research on genetic conditions and information on ongoing care.

There is currently no GeneReviews for AFF2.


Research Article Summaries

We currently do not have any article summaries for AFF2, but we add resources to our website as they become available.

The information available about AFF2 is limited, and families and doctors share a critical need for more information. As we learn more from children who have this gene change, we expect our list of resources and information to grow.

Full versions of published research articles can be found on PubMed. PubMed is a National Institutes of Health (NIH) online database that is free. It has a collection of both medical and scientific research articles. A PubMed search for AFF2 articles can be found here.

You can also visit the Simons Foundation’s SFARI Gene website to see information for researchers about this gene.


Research Opportunities

Simons Searchlight

Help the Simons Searchlight team learn more about AFF2 genetic changes by taking part in our research. You can learn more about the project and sign up here.


Family Stories

We do not currently have any stories from AFF2 families.

Click here to share your family’s story!