FOXP2-Related Syndrome

FOXP2-related syndrome happens when there are changes in the FOXP2 gene. These changes can keep the gene from working as it should.

Each family is different. A geneticist or genetic counselor can give you advice on the chance that this will happen again in your family.

The risk of having another child who has FOXP2-related syndrome depends on the genes of both biological parents. 

• If neither biological parent has the same genetic variant found in their child, the chance of having another child who has the syndrome is on average 1 percent. This 1 percent chance is higher than the chance of the general population. The increase in risk is due to the very unlikely chance that more of the mother’s egg cells or the father’s sperm cells carry the same genetic variant. 
• If one biological parent has the same genetic variant found in their child, the chance of having another child who has the syndrome is 50 percent. 

For a symptom-free brother or sister of someone who has FOXP2-related syndrome, the sibling’s risk of having a child who has FOXP2-related syndrome depends on the sibling’s genes and their parents’ genes. 

• If neither parent has the same genetic variant causing FOXP2-related syndrome, the symptom-free sibling has a nearly 0 percent chance of having a child who would inherit FOXP2-related syndrome. 
• If one biological parent has the same genetic variant causing FOXP2-related syndrome, the symptom-free sibling has a 50 percent chance of also having the same genetic variant. If the symptom-free sibling has the same genetic variant, their chance of having a child who has the genetic variant is 50 percent. 

For a person who has FOXP2-related syndrome, the risk of having a child who has the syndrome is about 50 percent.

As of 2026, about 66 people with FOXP2-related syndrome have been identified in a medical clinic.

People who have FOXP2-related syndrome might not look very different.

Scientists and doctors have only just begun to study FOXP2-related syndrome. At this point, there are no medicines designed to treat the syndrome. A genetic diagnosis can help people decide on the best way to track the condition and manage therapies. Doctors can refer people to specialists for:

• • Physical exams and brain studies
  • Genetics consults
  • Development and behavior studies
  • Other issues, as needed

A developmental pediatrician, neurologist, or psychologist can follow progress over time and can help:

• • Suggest the right therapies. This can include physical, occupational, speech, or behavioral therapy.
  • Guide individualized education plans (IEPs).

Specialists advise that therapies for FOXP2-related syndrome should begin as early as possible, ideally before a child begins school.

If seizures happen, consult a neurologist. There are many types of seizures, and not all types are easy to spot. To learn more, you can refer to resources such as the Epilepsy Foundation’s website: www.epilepsy.com/learn/types-seizures.

Learning and Speech

Some people with FOXP2-related syndrome had developmental delay or intellectual disability, and several had learning disabilities. Most people had speech delay and speech challenges as they aged, including impairment of expressive and receptive language abilities, verbal dyspraxia, having only a few words for communication, stuttering, and articulation issues. People usually developed their first words between 18 months and 7 years.

• 8 out of 40 people had developmental delay or intellectual disability (20 percent)
• 12 out of 24 people had learning disabilities (50 percent)
• 32 out of 37 people had speech delay (87 percent)
• 9 out of 24 people had articulation issues (38 percent)

Often people had a non-verbal IQ that was higher than their verbal IQ, and most people attended mainstream schooling. Many people had learning support in school, such as a teaching aide and an individualized learning plan.

• 14 out of 23 people attended mainstream schooling (61 percent)

Behavior

A few people with FOXP2-related syndrome had behavioral challenges, such as autism or features of autism, attention-deficit/hyperactivity disorder (ADHD), restricted interests and behavior, anxiety, depression, and obsessive-compulsive disorder.

• 8 out of 40 people had autism (20 percent)
• 5 out of 27 people had anxiety (19 percent)
• 6 out of 27 people had depression (22 percent)
• 2 out of 27 people had obsessive-compulsive disorder (7 percent)

Other medical features

More than 1 in 3 people with FOXP2-related syndrome had feeding difficulties as babies. Some had gross motor and fine motor impairments, sleep issues, hearing issues, low muscle tone, and a smaller than average head size (microcephaly).

• 10 out of 26 people had feeding difficulties (38 percent)
• 13 out of 26 people had gross motor impairments (50 percent)
• 13 out of 26 people had fine motor impairments (50 percent)
• 10 out of 24 people had sleep issues (42 percent)
• 2 out of 26 people had hearing issues (8 percent)

Simons Searchlight

Simons Searchlight is an online international research program, building an ever growing natural history database, biorepository, and resource network of over 175 rare genetic neurodevelopmental disorders. By joining their community and sharing your experiences, you contribute to a growing database used by scientists worldwide to advance the understanding of your genetic condition. Through online surveys and optional blood sample collection, they gather valuable information to improve lives and drive scientific progress. Families like yours are the key to making meaningful progress. To register for Simons Searchlight, go to the Simons Searchlight website at www.simonssearchlight.org and click “Join Us.”

• Learn more about Simons Searchlight – www.simonssearchlight.org/frequently-asked-questions
• Simons Searchlight webpage with more information on FOXP2 – www.simonssearchlight.org/research/what-we-study/foxp2