17p11.2 Duplication Syndrome
What is 17p11.2 duplication syndrome?
17p11.2 duplication-related syndrome happens when there are changes to the 17p11.2 gene. These changes can keep the gene from working as it should. The syndrome is also known as Potocki-Lupski syndrome.
Key Role
17p11.2 duplication syndrome affects communication, social, and learning skills.
Symptoms
People who have 17p11.2 duplication syndrome may have:
- Developmental delay
- Intellectual disability
- Attention issues
- Autism
- Low muscle tone
- Difficulty swallowing
- Failure to thrive
- Heart issues
What causes 17p11.2 duplication syndrome?
17p11.2 duplication syndrome is caused by an extra piece of chromosome 17, one of the body’s 46 chromosomes. Chromosomes are structures in our cells that house our genes. We inherit chromosomes from our parents. When the sperm from the father joins the egg from the mother, they form a single cell with 46 chromosomes — 23 from the mother and 23 from the father. This cell then makes many copies of itself.
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.
Dominant Inheritance
Children have a 50% chance of inheriting the genetic change
Child who has a de novo 17p11.2 duplication
Why does my child or I have 17p11.2 duplication syndrome?
No parent causes their child’s 17p11.2 duplication syndrome. We know this because no parent has any control over the chromosome 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 genetic change takes place on its own and cannot be predicted or stopped.
What are the chances that other family members or future children will have 17p11.2 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 17p11.2 duplication syndrome depends on the chromosomes of both birth parents.
- If neither birth parent has the same chromosome 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 chromosome change found in their child, the chance of having another child who has the syndrome is about 50 percent.
For a symptom-free sibling, a brother or sister, of someone who has 17p11.2 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 chromosome 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 17p11.2 duplication syndrome.
- If one birth parent has the same chromosome change found in their child who has the syndrome, the symptom-free sibling has a small chance of also having the same chromosome change.
- If the symptom-free sibling has the same chromosome change as the child who has the syndrome, the symptom-free sibling’s chance of having a child who has 17p11.2 duplication syndrome is about 50 percent.
For a person who has 17p11.2 duplication syndrome, the risk of having a child who has the syndrome is about 50 percent.
Do all people who have 17p11.2 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.
Will all of the people in a family that have 17p11.2 duplication syndrome have the same symptoms?
Not necessarily. Family members who have the same chromosome change can have different symptoms.
How many people have 17p11.2 duplication syndrome syndrome?
About 1 in 25,000 people have 17p11.2 duplication syndrome. The first case was found in 2007. 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 who have 17p11.2 duplication syndrome look different?
People who have 17p11.2 duplication syndrome may have slight changes in their facial features.
How is 17p11.2 duplication syndrome treated?
At this point, there are no medicines designed to treat 17p11.2 duplication 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
- Developmental 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 17p11.2 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/learn/types-seizures.
This section includes a summary of information from published articles. It highlights how many people have different symptoms. See the Sources and references section of this guide for a list of articles.
Behavior and development concerns linked to 17p11.2 duplication syndrome
Speech
Almost everyone who has the syndrome has speech delay. Speech skills may improve with age and speech therapy.
Learning
Most people have moderate intellectual disability.
Behavior
Attention issues, hyperactivity, and anxiety are common. Some people who have the syndrome have autism.
Medical and physical concerns linked to 17p11.2 duplication syndrome
Sitting and walking
Most people who have the syndrome have motor delays. Most can walk on their own by 2 years old.
Muscle tone
Low muscle tone is common.
Feeding and digestion issues
Difficulty feeding and swallowing are common.
Growth
Slow growth is common and may be linked to difficulty feeding. Some people have short height and lower than usual levels of growth hormone.
Heart
About 40 percent have heart issues, which are often present at birth. This can include atrial and ventral septal defects, a hole in the wall between the two upper or lower chambers of the heart. A few people have problems with heart rhythms that can be detected with a medical test called an electrocardiogram.
Sleep
Some people have breathing issues during sleep, including sleep apnea, in which breathing stops briefly during sleep.
Where can I find support and resources?
PTLS Foundation
The PTLS Foundation is a non-profit 501(c)(3) organization dedicated to supporting, bringing about awareness and educating the medical and educational community and families who have loved ones diagnosed with PTLS. Their mission is to increase public awareness, understanding and acceptance of Potocki-Lupski Syndrome (PTLS or Dup. 17p11.2) by providing information to families and caregivers of persons with PTLS, sharing research, and fostering partnerships with health care, education, and other service professionals.
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 17p11.2 duplication: www.simonssearchlight.org/research/what-we-study/17p11-2-duplication/
- Simons Searchlight Facebook page for 17p11.2 duplication: 17p11.2 Duplication Facebook Group
Sources and References
The content in this guide comes from a published article about 17p11.2 duplication syndrome. Below you can find details about the article, as well as a link to the full article.
- Potocki L. et al. Gene Reviews, (2017). Potocki-Lupski syndrome www.ncbi.nlm.nih.gov/books/NBK447920/#potocki-lupski