Understanding HNRNP Disorders
If you're here because your child or family member was recently diagnosed, take a breath—you're in the right place. We'll help you understand what HNRNP-Related Neurodevelopmental Disorders are, what they mean, and where to find support.
Mother Kaori Suzuki (head of Japan's HNRNP Family Foundation) holding her child Nozomi who has HNRNPH2-NDD
Start Here
Whether you're a parent, caregiver, or medical professional, we've organized the information to help you learn at your own pace.
Learn the Basics
Understand what HNRNP genes are and why they matter for brain development.
Start with the basicsFind Your Condition
Learn about the specific HNRNP disorder affecting your family.
Explore conditionsHow Genes Affect Development
Scroll to explore the journey from DNA to brain development
DNA
Your body's instruction manual
Every cell in your body contains DNA—a complete set of instructions for building and running your body. This double helix structure holds the blueprint of life.
RNA
The messenger molecules
RNA is a molecule that helps transfer the genetic information stored in DNA into actual working proteins. DNA is like the master blueprint, and RNA is like a copy of one page of that blueprint that the cell uses to build a specific protein.
Genes
Individual instructions
Genes are specific sections of DNA that provide instructions for making proteins. The HNRNP family includes 30+ genes that help cells process DNA into protein.
Amino Acids
The building blocks of proteins
Amino acids are the building blocks of proteins. They are the individual units that make up proteins. There are 20 different amino acids that can be combined in different ways to make proteins.
Proteins
The worker molecules
Proteins are the worker molecules that carry out the instructions encoded in genes. The hnRNP proteins help process RNA messages inside cells.
Brain Development
How it all connects
hnRNP proteins are especially important in the developing brain. They help provide the tools for neurons to grow, connect, and communicate. When these proteins don't work correctly, it can affect brain and other body system development.
HNRNP Disorders
What happens when things change
When there’s a change in an HNRNP gene, there is not enough properly working hnRNP protein. This affects how the brain and body develop and function.
A Family of Helper Genes
The HNRNPs are a family of about 30 related genes. Think of them as a team of helpers that work together inside your cells. Their main job is to process RNA—the messenger molecules that carry instructions from your DNA to build proteins.
What They Do
- Alternative splicingDeciding which version of a gene gets used
- RNA stabilityProtecting important messages from being destroyed
- Gene regulationControlling when and where genes are “turned on” or “off”
- Protein productionHelping turn RNA messages into working proteins
Why They Matter for the Brain
The brain is incredibly complex and relies heavily on precise gene regulation. HNRNP proteins are especially active in the developing brain, helping neurons grow, form connections, and communicate. When an HNRNP gene doesn't work properly, it can affect many aspects of brain development.
The HNRNP Family of Disorders
These conditions share similarities because the genes work together. We've color-coded them to show which are most closely related.
These disorders are currently being researched for potential inclusion in the HNRNP-RNDD family.
Why group them together?
These proteins work together inside cells, share similar structures, and can even compensate for each other. This means research breakthroughs for one condition may help others in the family.
Find Your Condition
Click on a condition to learn more about its specific features, research, and resources.
HNRNPC-RNDD
Gene: HNRNPC
HNRNPC-RNDD was first described in 2023. While other members of the HNRNP gene family were already linked to neurodevelo...
Learn More →PTBP1-RNDD
Gene: PTBP1
PTBP-related neurodevelopmental disorder (also called PTBP1-RNDD) is a rare genetic condition caused by changes in the P...
Learn More →HNRNPG-RNDD
Gene: RBMX
Two disorders have been described related to changes in the RBMX gene: Shashi-type intellectual disability and Gustavson...
Learn More →HNRNPH1-RNDD
Gene: HNRNPH1
HNRNPH1-RNDD was first described in 2018. While at first considered a type of Bain type intellectual disability (due to ...
Learn More →HNRNPH2-RNDD
Gene: HNRNPH2
HNRNPH2-RNDD was first described in 2016. Variants in HNRNPH2 on the X chromosome are associated with a neurodevelopment...
Learn More →Au-Kline Syndrome
Gene: HNRNPK
HNRNPK-related neurodevelopmental disorder, also called Au-Kline syndrome (AKS), is a rare genetic condition that affect...
Learn More →HNRNPR-RNDD
Gene: HNRNPR
HNRNPR-RNDD is a rare genetic condition that affects how a child grows, learns, and develops. Most individuals with this...
Learn More →HNRNPU-RNDD
Gene: HNRNPU
HNRNPU-related neurodevelopmental disorder is a rare genetic condition that affects how a child grows, learns, and devel...
Learn More →SYNCRIP-RNDD
Gene: SYNCRIP
SYNCRIP-related neurodevelopmental disorder (also called HNRNPQ-RNDD) is a rare genetic condition caused by changes in t...
Learn More →What's Next?
Now that you understand the basics, here are your next steps.
Newly Diagnosed Guide
A comprehensive guide for families who just received a diagnosis, including what to expect and how to find support.
Read the guideResearch & Science
Learn about current research, clinical trials, and the scientists working to understand these conditions.
Explore researchJoin Our Community
Connect with other families who understand what you're going through. You're not alone on this journey.
Connect nowHelpful Links
GeneReviews Glossary
Medical and genetics terms explained in plain language
Our Glossary
Terms specific to HNRNP disorders, written for families
Unique
Support organization for rare chromosome and gene disorders
Simons Searchlight
Registry for rare genetic neurodevelopmental disorders
NORD
National Organization for Rare Disorders