When people hear that something is “genetic,” it’s easy to imagine a single faulty gene causing the problem. That’s true for some rare conditions — but for most traits like ADHD, intelligence, or mental health, it’s a lot more complicated.
In this blog post, we’ll explain what a polygenic score is, why it matters, and why it only captures part of the picture.
What Is a Polygenic Score?
A polygenic score (PGS) is a way of estimating how your genetics might influence a certain trait — like your height, your risk of ADHD, or how long you stay in education.
It works by adding up the effects of many tiny genetic changes spread throughout your DNA. Each of these changes is called a SNP (single nucleotide polymorphism — basically, one-letter spelling differences in the DNA code).
On their own, these SNPs have almost no impact. But when you add thousands of them together, they can start to give a rough prediction.
What Can a Polygenic Score Tell You?
Polygenic scores can help predict things like:
- How likely someone is to develop ADHD
- Risk of conditions like diabetes or heart disease
- Likelihood of higher educational attainment
But these are statistical probabilities, not guarantees. And they’re only part of the picture.
Why Polygenic Scores Aren’t the Full Story
Polygenic scores only use common genetic variants — the ones that are easy to measure and happen frequently in the population.
They don’t include:
- Rare variants (which can have large effects on their own)
- Structural changes in the genome (like big deletions or duplications)
- Gene–gene interactions (where combinations of variants have unexpected effects)
So even if your polygenic score says you’re “low risk,” you could still be affected by rare genetic factors that weren’t measured.
What’s Changing Now?
Recent studies are starting to combine polygenic scores with rare variant data. For example, researchers have found that people with damaging rare variants in certain genes tend to have:
- Lower educational outcomes
- More health problems
- Higher rates of disability or cognitive difficulties
But they also found that if someone had both rare variants and a high polygenic score, the effects could partially cancel out — or add up.
This suggests the best approach is to look at:
- Common variants (polygenic score)
- Rare damaging variants
- Environmental factors and life experiences
Why This Matters for ADHD and Mental Health
In conditions like ADHD, no single gene explains the whole picture. But patterns of common and rare variants can help us understand someone’s underlying biology.
This can guide:
- More tailored treatment plans
- Better understanding of how symptoms show up
- More compassionate, less judgemental care
When we see ADHD and other conditions as polycausal — influenced by many small things — we move away from blaming and toward understanding.
At ADHD Consultancy, We’re Passionate About Polycausality
At ADHD Consultancy, we believe that no two people experience ADHD the same way — and no single cause explains it. That’s why we’ve developed a Polycause Panel for ADHD: a carefully selected collection of SNPs that reflect our core domains of interest:
- Dopamine regulation
- Inflammation and immune reactivity
- Histamine sensitivity
- Connective tissue fragility
- Circadian rhythm and hormonal disruption
- Language and auditory processing vulnerability
Dr Helen Read offers all clinic patients a free, detailed genetic analysis that:
- Explains their individual SNP patterns
- Identifies clinical and lifestyle strategies that may help
- Connects genetic findings to lived experience
- Highlights medication responses, pacing strategies, dietary adjustments, and hormonal considerations
Your results also contribute to our ongoing research into ADHD phenotypes, gendered symptom expression, and the intersection of neurobiology, inflammation, and cognition.
We believe that better understanding leads to better care — and more dignity, accuracy, and compassion in how ADHD is diagnosed and supported.
Final Thought
Polygenic scores are an exciting step forward. But they’re not destiny. They’re just one part of a much bigger story.
As science improves, we’ll get better at combining different types of genetic data to build a fuller picture of each person — not just for diagnosis, but for care that really fits.