Genes and Cerebral Palsy

Understanding the science and what it could mean for families

By Amy Hogan and The Liggins Institute

For many years, the cause of Cerebral Palsy (CP) – Hōkai Nukurangi has been explained as the result of early brain injury, occurring before, at or after birth. Events causing CP can include  premature birth, infections or other maternal illnesses during pregnancy, or a lack of oxygen around the time of birth. While these are still important causes, for many children, the cause remains unclear. New research shows another factor can be part of the story: genes.

Genes are the body’s instruction manual. They guide growth, development, and the way cells work together. Sometimes, small differences in genes can affect how the brain develops, even before birth. For some people with CP, these genetic changes may be a key part of the reason why the  condition occurs.

This doesn’t mean that CP is now seen as “genetic only”. CP is complex and often has multiple contributing factors. Sometimes genetics or birth events play a role, and often both are intertwined in causing CP. What’s new is that modern technology now allows researchers to study DNA in much greater detail, helping us better understand why CP happens and how to support people across their lifespan. In Aotearoa, New Zealand CP researchers are at the beginning of our efforts to understand the role that genes may or may not play in how CP presents and the ongoing experience across the lifespan.

What are genes?

Genes are made of DNA, the material inside every cell that tells the body how to grow and function. Each person has around 20,000 genes, and we inherit most of them from our parents.

Sometimes, changes occur in genes. Scientists call these changes variants or mutations . Many variants are harmless, while others can affect how the body develops or works. Genetic variants can be:

• Inherited – passed from one or both parents.
• De novo – appearing for the first time in the child, not present in the parents’ DNA.

If a genetic change affects how the brain develops, how nerve cells connect, or how movement is controlled, it may increase the risk of developing CP. Current research is also asking whether some genetic variants influence specific features of CP, such as muscle tone, seizures, or bone health.

Genes and CP – fact and fiction

Fact: Research suggests that around 14%–30% of people with CP may have a genetic change that contributed to their condition. The wide range exists because studies use different methods and include different groups of people. As research improves, these estimates are likely to become more precise.

Fiction: There’s a single “CP gene”. In reality, scientists have identified hundreds of genes where variants/mutations may increase the risk of CP. Each genetic change is usually rare, and different genes can affect different biological pathways. Some may also be linked to other health conditions.  

Fact: Many genetic changes in CP are de novo. Parents didn’t “cause” these changes and couldn’t have prevented CP in their child.

Fiction: If CP has a genetic cause, it’s no longer CP. The diagnosis is based on symptoms (motor difficulties from early brain development), not cause.

Fact: Genes are one part of the picture. Premature birth, infections, or other complications can still be important – and sometimes these factors work together with genetic vulnerabilities.

The science of CP genomics

(Genomics is the study of the full set of a person’s genes.)

Scientists have  studied the effect of genes on health conditions for many years. Recent advances in technology have made genetic testing faster, more accurate, and more affordable. This has allowed researchers to paint a comprehensive “genetic picture” of how gene differences may influence conditions like CP. The ability to bring this knowledge to a condition like CP is still relatively new, particularly in Aotearoa New Zealand.

In CP research, scientists often study:

• The child’s DNA.
• The DNA of both parents, to identify whether variants are inherited or de novo (new).
• Large groups of people with CP to look for patterns that help explain risk and variations in symptoms.

Key findings so far

• Many genes involved: More than 300 genes have been reported in CP or similar conditions. Over 160 are considered strongly linked to CP based on current evidence.
• Most variants are rare: Many genetic changes are unique to person or family.
• Larger DNA changes can matter: Some people with CP have small sections of DNA that are missing or duplicated. These are called copy number variants (CNVs) and can affect brain development.
• Overlap with other conditions: Some genes linked to CP are also associated with epilepsy, autism, or intellectual disability. This can explain why some people with CP have multiple diagnoses.

It’s important to note that while intervention is the key goal, cases like these of direct outcomes are still relatively rare, and the current focus is on building the understanding of CP genetics on a broader scale so that we can build up our information before putting the knowledge into widespread practice.

The International Cerebral Palsy Genomics Consortium (ICPGC)

Because each gene change is rare, researchers need to work together globally. The ICPGC is an international network of scientists, clinicians, and advocates aiming to:

• Pool genetic and clinical data from around the world
• Build gene panels specific to CP
• Improve early diagnosis
• Lay the foundation for personalised treatments.

By combining cases, they can spot patterns no single study could detect alone.

Why this (potentially) matters for families

1. Finding answers
Many families live with uncertainty about why CP happened. A genetic diagnosis may give a clear explanation, often reducing guilt or blame.

2. Guiding care
Genetic results can highlight other health issues to watch for – such as seizures or heart conditions – allowing for earlier monitoring and treatment.

3. Connecting with others
Even rare genetic findings can connect families worldwide who share similar experiences and challenges.

4. Shaping therapy
In some cases, knowing the gene involved can guide therapy choices, medication, or management plans.

Genetic testing – how it works

• Sample: Usually, a blood or saliva sample from the person with CP, and sometimes parents.
• Analysis: DNA is examined for rare changes – either in all genes (whole exome/genome) or a panel of known CP-related genes.
• Results: May take many months. Sometimes they provide a clear answer; other times, they add to research but don’t immediately change care.
• Information feedback: there are different ways for families to get information about their testing. This is generally explained before the study or clinical trial begins. There is also work done with genetic counsellors on how people make sense of the information they are receiving.

Not all families will be offered testing, but the availability of tests is becoming more common as information, awareness, and advocacy grow.

The New Zealand context

Genetic research in CP is very new in Aotearoa New Zealand. Steps so far include:

• The Liggins Institute, University of Auckland – is conducting a research study to look at CP genomics within Aotearoa New Zealand’s population with recruitment planned to commence in the coming months.
• The NZ CP Register, Starship Children’s Health – is a database for people with CP that can store genetic information and which could support future genetics research.
• Australian links – Aotearoa New Zealand clinicians are involved in Australian CP genomics groups, connecting local families to larger research networks.
• Global partnerships – in the future, individuals with CP in Aotearoa New Zealand who chose to participate could contribute their data to the ICPGC and support shared discoveries

CP genomics research study

The Liggins Institute in collaboration with Te Toka Tumai |Starship Children’s and Auckland City Hospital and the NZ Cerebral Palsy Register are conducting a study using DNA sequencing to improve our understanding of the genetics of cerebral palsy in Aotearoa | New Zealand.

The aim of this study is to attempt to identify genetic changes increasing the risk for CP in individuals living with cerebral palsy. The research team wants to understand if knowing the genetic diagnosis can improve the quality of life for children and families living with cerebral palsy.

The study has been approved by the Health and Disability Ethics Committee, Ethics committee reference: 2025 FULL 24103. The study will be open to children and individuals living with cerebral palsy, and their families.

What’s involved if you choose to take part?

You would meet with a genetic counsellor or clinical geneticist who will explain the study to you, ask you some simple questions, and obtain your consent to be part of the study. Your information will be reviewed by the project team to confirm the study is right for you.

If you are eligible, you will be asked to:

• Consent for review of your clinical record
• Consent to be registered on the New Zealand Cerebral Palsy Register (NZCPR) and agree to have any CP-related genetic testing results included in the record
• Answer questions about you or your child’s past medical history
• Have two blood samples collected for whole genome sequencing
• Attend a follow up visit with a genetic counsellor and/or geneticist to discuss the results of your test
• Consent to future contact as new information about genetic causes and treatments become available.

For more information on this study please email – CPgenes@auckland.ac.nz

Looking ahead

In the future, research suggests we may see:

• Genetic testing used more often for some people with CP, especially when the cause is unclear or when other conditions are present.
• Earlier and more personalised support, where genetic information helps guide monitoring, therapy choices, or clinical follow-up.
• Precision medicine approaches, where care is better tailored to an individual’s biological profile. For CP, this is likely to focus on managing risk, preventing complications, and supporting long-term health rather than curing the condition.
• Improved screening and medical surveillance, allowing clinicians to identify higher risk for specific features of CP, such as hip displacement, epilepsy, or changes in bone health.

While genetics won’t replace therapy, inclusion, education, or day-to-day support, it can offer powerful new tools for understanding and managing CP. For families in Aotearoa New Zealand, being part of this global research effort helps ensure that these advances can be adopted locally as evidence grows.

Summary points:

• Genetics is an emerging but important part of CP research
• Many different genes can be involved; and most genetic variants are rare. Genetic testing can provide answers, guide care, and connect families with others who share similar experiences
• Aotearoa New Zealand is at the starting point but linked into international networks
• The (very) long-term vision is more personalised and precise care for every person with CP, alongside strong therapeutic and community support.

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A shorter version of this article was originally published in the March 2026 edition of The Review magazine.

 

For more information:
Melanie Louden
Communications Manager
melanie@cpsociety.org.nz
Mobile: 022 087 819