17p13.3 Duplication Syndrome
What is 17p13.3 duplication syndrome?
17p13.3 duplication syndrome happens when there are changes to the 17p13.3 gene. These changes can keep the gene from working as it should.
Key Role
17p13.3 duplication syndrome can affect communication, social, and learning skills.
Symptoms
People who have 17p13.3 duplication syndrome may have:
- Intellectual disability
- Low muscle tone
- Autism
What causes 17p13.3 duplication syndrome?
17p13.3 duplication syndrome happens when someone has an extra piece of chromosome 17, one of the body’s 46 chromosomes. Chromosomes are structures in our cells that house our genes.
Some people inherit a genetic change from a parent. In other people, small mistakes can occur when genes are being copied. Parts of the chromosomes can break off, make extra copies, or end up in a different order than expected. When this happens, it is called a “de novo”, or new, change. The child can be the first in the family to have the genetic change.
Do all people with 17p13.3 duplication syndrome have symptoms?
Not necessarily. Some people do not have any symptoms. Some people may not learn that they have this genetic change until it is found in their children.
Child who has genetic change in 17p13.3 gene
Why does my child have a change in the 17p13.3 gene?
No parent causes their child’s 17p13.3 duplication syndrome. We know this because no parent has any control over the gene changes that they do or do not pass on to their children. Please keep in mind that nothing a parent does before or during the pregnancy causes this to happen. The gene change takes place on its own and cannot be predicted or stopped.
What are the chances that other family members of future children will have 17p13.3 duplication syndrome?
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 17p13.3 duplication syndrome depends on the genes of both birth parents.
- If neither birth parent has the same gene change 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 change in the gene.
- If one birth parent has the same gene change found in their child, the chance of having another child who has the syndrome is 50 percent.
For a symptom-free sibling, a brother or sister, of someone who has 17p13.3 duplication syndrome, the risk of having a child who has the syndrome depends on the symptom-free sibling’s genes and their parents’ genes.
- If neither parent has the same gene change found in their child who has the syndrome, the symptom-free sibling has a nearly 0 percent chance of having a child who has 17p13.3 duplication syndrome.
- If one birth parent has the same gene change found in their child who has the syndrome, the symptom-free sibling has a small chance of also having the same gene change. If the symptom- free sibling has the same gene change as their sibling who has the syndrome, the symptom-free sibling’s chance of having a child who has 17p13.3 duplication syndrome is 50 percent.
For a person who has 17p13.3 duplication syndrome, the risk of having a child who has the syndrome is about 50 percent.
How many people have 17p13.3 duplication syndrome?
As of 2020, doctors had described about 50 people who have 17p13.3 duplication syndrome. The first case was found in 2009. There are likely many more undiagnosed people who have the syndrome. Scientists expect to find more people who have the syndrome as access to genetic testing improves.
Do people with 17p13.3 duplication syndrome look different?
People who have 17p13.3 duplication syndrome may look a little bit different. Appearance can vary. Some people have a long face. Some children have features that are linked to low muscle tone in their face, such as droopy skin around the eyes and the eyelid.
How is 17p13.3 duplication syndrome treated?
Scientists and doctors have only just begun to study 17p13.3 duplication 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 17p13.3 duplication 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: epilepsy.com/…t-is-epilepsy/seizure-types
17p13.3 duplication syndrome is very rare. Doctors and scientists have just recently begun to study it. As of 2020, studies found around 50 people who have 17p13.3 duplication syndrome.
This section includes a summary of information from major published articles. It highlights how many people have different symptoms. To learn more about the articles, see the Sources and references section of this guide.
Behavior and development concerns linked to 17p13.3 duplication syndrome
Learning
Two-thirds of people who have 17p13.3 duplication syndrome have intellectual disability. Most of these cases are mild.
Behavior
Almost one-third have autism. Some people have other behavior issues, including attention deficit hyperactivity disorder, temper tantrums, occasional obsessive compulsive disorder, and food seeking behaviors.
Medical and physical concerns linked to 17p13.3 syndrome
Muscle Tone
Almost everyone who has 17p13.3 duplication syndrome has low muscle tone, also known as hypotonia.
Where can I find support and resources?
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 17p13.3 duplications: www.simonssearchlight.org/research/what-we-study/17p13-3-duplication
- Simons Searchlight Facebook group: 17p13.3 Duplication Facebook group
Sources and References
- PubMed search for 17p13.3 duplication syndrome https://pubmed.ncbi.nlm.nih.gov/?term=17p13.3+Duplication