What are 2P16.3 (NRXN1) deletions?
2p16.3 (NRXN1) deletions are a rare genetic condition caused by a tiny missing part of one of the body’s 46 chromosomes, called chromosome 2. This deletion can occur spontaneously, or can be inherited.
There is a lot of variation between individuals who have a NRXN1 deletion, even within the same family. Some people with NRXN1 deletions can develop conditions such as autism, schizophrenia and intellectual disability, while others may not develop any mental health condition. Some research suggests that this is linked to the location and size of the deletion within the NRXN1 gene.
Common characteristics identified among people with NRXN1 deletions include:
- Intellectual disability or developmental delay
- Speech and language delay
- Sometimes also seizures
What does the NRXN1 gene do?
The NRXN1 gene is involved in producing a protein, called neurexin-1, which has an important role in the function of nerve cells in the brain, called neurons. Neurons are the building blocks of the brain, and they communicate with each other across junctions, called synapses.
A deletion within the NRXN1 gene may cause changes in how neurons function and communicate with each other in the brain, which could have broad effects on how a person thinks and behaves.
The Synaptic Gene (SynaG) project
The goal of the SynaG study is to investigate brain development, cognition, emotion and social skills in people with NRXN1 deletions to better understand if there are any features that are characteristic of NRXN1 deletions. We know that some people may develop a neurodevelopmental condition such as autism, while others do not.
We compare to individuals who have autism with no known genetic condition, and to typically developing individuals without any rare genetic condition or diagnosis of a neurodevelopmental condition.
This project is in collaboration with researchers at King’s College London, to investigate rare genetic conditions associated with neurodevelopmental conditions such as autism. This study is part of a European consortium called AIMS-2-TRIALS
(Click Here to find out more).
Who can participate in the study?
Any child, adolescent, or adult over the age of two years:
- with a NRXN1 deletion (located at 2p16.3).
- with a diagnosis of autism and no known rare genetic condition.
- without a rare genetic condition or diagnosis of a neurodevelopmental condition.
What does the study involve
We use multiple measures to study relationships between genetics, brain structure and function, and how a person thinks or behaves. These measures include:
- Pen-and-paper tasks, computerised tasks, and questionnaires to measure thinking skills and behaviour;
- Blood and saliva samples, which allow researchers to study a person’s genes;
- Tracking eye movements as a way to understand cognition i.e. how people think, perceive and learn about the world;
- Brain scans with magnetic resonance imaging (MRI) scanners, to measure brain structure and function, and to assess connections between brain regions;
- EEG, which is a method to record the brain’s electrical activity while people rest or engage in a tasks. EEG involves placing small gel sensors on the head that are painless.
We hope that a better understanding of the links between NRXN1 deletions, brain development and behaviour will help us to better support people with NRXN1 deletions and neurodevelopmental conditions.
You can contact us at recruitmentNRG@tcd.ie for more information about participation.
Ned and Nelly's NRXN1 Deletion Story (pdf): Currently, there isn’t a lot information about NRXN1 deletions that is easy to understand for parents/caregivers or their children when they receive a diagnosis. We created a storybook, called “Ned & Nelly’s NRXN1 Deletion Story”, to help families to learn about this rare condition together.