2q37 Deletion Syndrome
2q37 deletion syndrome is also called 2q37 microdeletion. For this webpage, we will be using the name 2q37 deletion syndrome to encompass the wide range of variants observed in the people identified.
What is 2q37 deletion syndrome?
2q37 deletion syndrome happens when a person is missing a piece of chromosome 2, one of the body’s 46 chromosomes. Chromosomes are structures in our cells that house our genes. The missing piece can affect learning and how the body develops.
Key Role
The 2q37 deletion region plays a role in brain development.
Symptoms
2q37 deletion syndrome can affect communication, social, and learning skills. People who have 2q37 deletion syndrome may have:
- Obesity
- Developmental delay
- Intellectual disability
- Sleep disturbance
- Self-injury behavior
- Aggression
- Attention-deficit/hyperactivity disorder (ADHD)
- Low muscle tone
- Seizures
- Autism
- Heart issues
- Gastrointestinal problems
- Recurrent ear infections
- Breathing issues
What causes 2q37 deletion syndrome?
2q37 deletion syndrome is a genetic condition, which means that it is caused by variants in genes. Our genes contain the instructions, or code, that tell our cells how to grow, develop, and work. Every child gets two copies of the 2q37 gene: one copy from their mother’s egg, and one copy from their father’s sperm. In most cases, parents pass on exact copies of the gene to their child. But the process of creating the egg or sperm is not perfect. A change in the genetic code can lead to physical issues, developmental issues, or both.
Sometimes a spontaneous variant happens in the sperm, egg or after fertilization. When a brand new genetic variant happens in the genetic code is called a ‘de novo’ genetic variant. The child is usually the first in the family to have the genetic variant.
De novo variants can take place in any gene. We all have some de novo variants, most of which don’t affect our health. But because 2q37 plays a key role in development, de novo variants in this gene can have a meaningful effect.
Research shows that 2q37 deletion syndrome is often the result of a de novo variant in 2q37. Many parents who have had their genes tested do not have the 2q37 genetic variant found in their child who has the syndrome. In some cases, 2q37 deletion syndrome happens because the genetic variant was passed down from a parent.
Autosomal dominant conditions
2q37 deletion syndrome is an autosomal dominant genetic condition. This means that when a person has the one damaging variant in 2q37 they will likely have symptoms of 2q37 deletion syndrome. For someone with an autosomal dominant genetic syndrome, every time they have a child there is a 50 percent chance they pass on the same genetic variant and a 50 percent chance they do not pass on the same genetic variant.
Autosomal Dominant Genetic Syndrome
Do all people with 2q37 deletion 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.
Why does my child have a change in the 2q37 gene?
No parent causes their child’s 2q37 deletion 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 2q37 deletion 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 2q37 deletion 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 2q37 deletion syndrome, the sibling’s risk of having a child who has 2q37 deletion syndrome depends on the sibling’s genes and their parents’ genes.
- If neither parent has the same genetic variant causing 2q37 deletion syndrome, the symptom-free sibling has a nearly 0 percent chance of having a child who would inherit 2q37 deletion syndrome.
- If one biological parent has the same genetic variant causing 2q37 deletion 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 2q37 deletion syndrome, the risk of having a child who has the syndrome is about 50 percent.
How many people have 2q37 deletion syndrome?
As of 2024, at least 200 people with 2q37 deletion syndrome have been identified in medical research. The first case was found in 1995. Scientists expect to find more people who have the syndrome as access to genetic testing improves.
Do people who have 2q37 deletion syndrome look different?
People who have 2q37 deletion syndrome may look different. Appearance can vary and can include some but not all of these features:
- Broad, round face
- Thin upper lip
- Protruding forehead
- Arched eyebrows
- Short height
- Short third, fourth, and fifth fingers, also known as brachydactyly type E
How is 2q37 deletion syndrome treated?
Scientists and doctors have only just begun to study 2q37 deletion 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 2q37 deletion 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
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 2q37 deletion syndrome
Depending on the specific 2q37 deletion, the 2q37 region may have up to 197 genes deleted.
The 2q37 region is divided into sub-regions: 2q37.1, 2q37.2, and 2q37.3. The deletion size and type can be highly variable. The information below includes people in all categories.
Speech and Learning
People with 2q37 deletion syndrome had developmental delay or intellectual disability and speech delay.
- 89 out of 112 people had developmental delay or intellectual disability (80 percent)
- 45 out of 103 people had speech delay (45 percent)
Behavior
Behavioral disorders occurred in people with 2q37 deletion syndrome, including features of autism, hyperactivity, repetitive behaviors, friendly disposition, aggressive behavior, and self-mutilation.
- 31 out of 103 people had features of autism (30 percent)
- 16 out of 103 people had hyperactivity (16 percent)
- 24 out of 103 people had repetitive behaviors (23 percent)
- 12 out of 103 people had friendly disposition (12 percent)
- 12 out of 103 people had aggressive behavior (12 percent)
- 12 out of 103 people had self-mutilation (12 percent)
Brain
People with 2q37 deletion syndrome reported having various neurological issues. People sometimes had seizures, lower than average muscle tone, or brain changes observed on magnetic resonance imaging (MRI).
- 17 out of 103 people had seizures (17 percent)
- 33 out of 112 people had lower than average muscle tone (30 percent)
- 10 out of 103 people had brain changes on MRI (10 percent)
Medical and physical concerns linked to 2q37 deletion syndrome
Physical features
There were various physical findings identified in people with 2q37 deletion syndrome.
- 64 out of 103 people had overall extremity defects (62 percent)
- 49 out of 103 people had brachydactyly type E (48 percent)
- 40 out of 103 people had short fourth metacarpal (39 percent)
- 30 out of 103 people had short fourth metatarsal (29 percent)
- 26 out of 103 people had short fifth metacarpal (25 percent)
- 18 out of 103 people had small feet (17 percent)
- 17 out of 103 people had short third metacarpal (17 percent)
- 16 out of 103 people had small hands (16 percent)
Gastrointestinal and genitourinary issues
About 1 in 4 people with 2q37 deletion syndrome had gastrointestinal/genitourinary issues, mainly umbilical or inguinal hernias.
- 25 out of 103 people had gastrointestinal/genitourinary issues (24 percent)
Weight issues
People with 2q37 deletion syndrome were at risk of developing obesity.
- 37 out of 112 people had obesity (33 percent)
Where can I find support and resources?
2q37 Deletion Rare Chromosome Disorder
Unique
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 2q37 deletion- www.simonssearchlight.org/research/what-we-study/2q37-deletion
- Simons Searchlight Facebook group- 2q37 Deletion Facebook group
Sources and References
- Gavril, E. C., Nucă, I., Pânzaru, M. C., Ivanov, A. V., Mihai, C. T., Antoci, L. M., Ciobanu, C. G., Rusu, C., & Popescu, R. (2023). Genotype-phenotype correlations in 2q37-deletion syndrome: An update of the clinical spectrum and literature review. Genes (Basel), 14(2), 465. https://pubmed.ncbi.nlm.nih.gov/36833393/
- Le, T. N., Williams, S. R., Alaimo, J. T., & Elsea, S. H. (2019). Genotype and phenotype correlation in 103 individuals with 2q37 deletion syndrome reveals incomplete penetrance and supports HDAC4 as the primary genetic contributor. American Journal of Medical Genetics Part A, 179(5), 782-791. https://pubmed.ncbi.nlm.nih.gov/30848064/
- Leroy, C., Landais, E., Briault, S., David, A., Tassy, O., Gruchy, N., Delobel, B., Grégoire, M. J., Leheup, B., … & Doco-Fenzy, M. (2013). The 2q37-deletion syndrome: An update of the clinical spectrum including overweight, brachydactyly and behavioural features in 14 new patients. European Journal of Human Genetics, 21(6), 602-612. https://pubmed.ncbi.nlm.nih.gov/23073310/