JARID2-Related Syndrome
What is JARID2-related syndrome?
JARID2-related syndrome happens when there are changes in the JARID2 gene. These changes can keep the gene from working as it should.
Key Role
The JARID2 gene plays an important role in human development.
Symptoms
Because the JARID2 gene is important for many parts of the body, some people may have:
- Intellectual disability
- Learning issues
- Developmental delay
- Autism or features of autism
- Behavior issues
- Speech issues
What causes JARID2-related syndrome?
JARID2-related 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 JARID2 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 JARID2 plays a key role in development, de novo variants in this gene can have a meaningful effect.
Research shows that JARID2-related syndrome is often the result of a de novo variant in JARID2. Many parents who have had their genes tested do not have the JARID2 genetic variant found in their child who has the syndrome. In some cases, JARID2-related syndrome happens because the genetic variant was passed down from a parent.
Autosomal dominant conditions
JARID2-related syndrome is an autosomal dominant genetic condition. This means that when a person has the one damaging variant in JARID2 they will likely have symptoms of JARID2-related 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
Why does my child have a change in the JARID2 gene?
No parent causes their child’s JARID-related 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 JARID2-related 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 JARID2-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 JARID2-related syndrome, the sibling’s risk of having a child who has JARID2-related syndrome depends on the sibling’s genes and their parents’ genes.
- If neither parent has the same genetic variant causing JARID2-related syndrome, the symptom-free sibling has a nearly 0 percent chance of having a child who would inherit JARID2-related syndrome.
- If one biological parent has the same genetic variant causing JARID2-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 JARID2-related syndrome, the risk of having a child who has the syndrome is about 50 percent.
How many people have JARID2-related syndrome?
As of 2024, over 30 people in the world with JARID2-related syndrome have been described in medical research. The oldest person reported in the literature was 37 years old.
Do people who have JARID2-related syndrome look different?
People who have JARID2-related syndrome may look different. Appearance can vary and can include some but not all of these features:
- Lower than average muscle tone
- Deep-set eyes
- Bulbed tip nose
- Fuller than average lips
- Foot and finger abnormalities
How is JARID2-related syndrome treated?
Scientists and doctors have only just begun to study JARID2-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 JARID2-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: 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 JARID2-related syndrome
Behavior
About one-half of people have features of autism, and some meet the clinical level of an autism diagnosis.
- 10 out of 18 people have features of autism (56 percent).
- 5 out of 25 people have an autism diagnosis (20 percent).
Learning
Many people have some level of intellectual disability. Almost all people have developmental delays.
- 14 out of 25 have intellectual disability (56 percent).
- 23 out of 25 have developmental delays (92 percent).
Development
Many people have low muscle tone, and some have walking issues.
- 6 out of 18 have low muscle tone (33 percent).
- 5 out of 25 people have walking issues (20 percent).
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 JARID2: www.simonssearchlight.org/research/what-we-study/jarid2
- Simons Searchlight Facebook group: https://www.facebook.com/groups/370944638965135
Sources and References
- Cadieux-Dion M, Farrow E, Thiffault I, et al. Phenotypic expansion and variable expressivity in individuals with JARID2-related intellectual disability: A case series. Clin Genet. 2022;102(2):136-141. doi:10.1111/cge.14149
- van der Laan L, Rooney K, Haghshenas S, et al. Functional Insight into and Refinement of the Genomic Boundaries of the JARID2-Neurodevelopmental Disorder Episignature. Int J Mol Sci. 2023;24(18):14240. Published 2023 Sep 18. doi:10.3390/ijms241814240
- Verberne EA, van der Laan L, Haghshenas S, et al. DNA Methylation Signature for JARID2-Neurodevelopmental Syndrome. Int J Mol Sci. 2022;23(14):8001. Published 2022 Jul 20. doi:10.3390/ijms23148001
- Verberne EA, Goh S, England J, et al. JARID2 haploinsufficiency is associated with a clinically distinct neurodevelopmental syndrome. Genet Med. 2021;23(2):374-383. doi:10.1038/s41436-020-00992-z