About ITSN1
About ITSN1-related conditions
ITSN1-related conditions are caused by genetic variants in a gene called ITSN1. This gene provides instructions for making a protein called Intersectin-1, which plays an important role in how brain cells (neurons) communicate and stay healthy.
Intersectin-1 is essential for a process called endocytosis. Endocytosis allows cells to recycle receptors, signaling molecules, and other materials at the cell surface. In neurons, this process is critical for communication between cells and for maintaining the internal structure of the cell. When ITSN1 does not function as expected, these processes can be disrupted, which can affect brain development and long-term brain function.
How ITSN1 variants arise
Variants in ITSN1 can occur in different ways:
- De novo variants, meaning the genetic change is new in the affected individual and was not inherited from either parent.
- Inherited variants, where the change is passed down from a parent.
Both forms have been observed in individuals with ITSN1-related conditions.
Because ITSN1-related conditions have only recently been recognized, the true frequency is not yet known. As genetic testing becomes more widely used, more children and adults with ITSN1 variants are being identified worldwide.
A Spectrum of Associated Features
ITSN1-related conditions do not look the same in every person. Instead, they appear to fall along a spectrum, with features that can emerge at different stages of life.
Features reported to date include:
- Neurodevelopmental differences
- Autism spectrum disorder
- Developmental delay or developmental regression
- Attention-deficit/hyperactivity disorder (ADHD)
- Seizures (reported in a subset of individuals)
- Neurodegenerative disease
- Parkinson's disease (variants in all of ITSN1)
Not every individual will have all of these features. Some may present primarily with childhood-onset neurodevelopmental differences, while others may develop symptoms later in adulthood. Understanding why ITSN1 variants can be associated with both neurodevelopmental disorders and Parkinson’s disease is an active area of research.
What is Known—and What is Still Being Studied
Researchers know that ITSN1 is essential for normal neuronal function, but many important questions remain unanswered, including:
- How different ITSN1 variants lead to different symptoms
- Why some individuals are affected in childhood, while others develop symptoms later in life
- How ITSN1 dysfunction contributes to Parkinson's disease biology
Answering these questions is critical for developing targeted therapies in the future.
Treatment and Care
At present, there is no cure for ITSN1-related conditions. Treatment focuses on:
- Managing symptoms
- Supporting learning, development, and quality of life
- Anticipating and monitoring medical concerns as individuals age
Care is best provided by a multidisciplinary medical team, which may include neurologists, developmental specialists, therapists, and other healthcare professionals depending on individual needs.
Why Research Participation Matters
Because ITSN1-related conditions are rare and newly defined, research participation is essential. Studies that include children, adults, and families help researchers:- Better define the full clinical spectrum
- Understand how symptoms change over time
- Identify biological pathways that could be targeted by future treatments
Each participant contributes valuable information that may benefit not only their own family, but others affected by ITSN1 variants now and in the future.
If you are interested in participating in ITSN1 research, please contact us or visit our research study page.
Getting Support
Receiving a genetic diagnosis can feel overwhelming. You are not alone. We are committed to providing clear information, answering questions, and helping families connect with appropriate resources and research opportunities.
If you would like to learn more or get involved, please contact us.
Disclaimer
This website provides general information about the ITSN1 gene and is not intended to replace professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with any questions you may have regarding a medical condition.