Most people, it turns out, carry a high genetic risk for about three common diseases — even if they never develop any of them. That is the striking finding of a new study of nearly one million genomes, led by the University of Exeter and published in Genome Medicine, which describes the “average” human genome for the first time.
The study, reported on 22–24 October 2026, does not say most people will become ill. It says something subtler and, for wellness, more useful: genetic variation is normal, genetic risk is common, and a risk score alone is not a diagnosis.
FAKTA
- Study: “The average individual genome: a survey of nearly 1 million whole-genome sequences”, published in Genome Medicine, led by the University of Exeter.
- Data: Nearly one million individuals from two major biobanks — the UK Biobank and the US All of Us programme.
- Headline: Most people would be categorised as at high genetic risk for around three of 28 common conditions, including diabetes, cardiovascular disease and schizophrenia.
- Genome facts: About five million variants per genome; about 10,000 variants that alter gene sequences; one to three rare variants previously shown to cause serious genetic diseases; about 50 rare variants of uncertain clinical relevance.
- Key caution: Carrying a variant does not mean developing the condition; symptoms, family history, clinical findings and environment all matter.
Genetic risk common diseases
Senior author Caroline Wright of the University of Exeter said whole-genome sequencing has become an important tool for diagnosing genetic diseases, while genetic screening is increasingly explored to predict future disease risk. She noted that people may be unaware of the extent of genetic variation in their genomes, and that understanding the expected range could help clinicians and patients interpret findings more effectively.
Every person’s genome contains around five million variants — DNA locations that differ between individuals. Most are biologically neutral, the researchers found; about 10,000 alter gene sequences, with effects ranging from lactose intolerance to drug response.
What “high risk” really means
The team analysed polygenic risk scores, which combine all known genetic factors for a disease. Across 28 common conditions, most people scored as high risk for about three. But the team did not investigate participants’ health status, so many of those people may have no disease at all — a point the researchers stress.
That gap between score and sickness is the study’s wellness message: a genetic result must be read in context. A score is a prompt for conversation with a clinician, not a verdict.
A limitation to keep in view
The study also acknowledged a representativeness limit: participants in the analysed biobanks were disproportionately of Western European ancestry, highlighting the need for more genetically diverse populations in future research. Risk scores built mainly on one ancestry may not transfer evenly to others.
The work was supported by the Medical Research Council, the Wellcome Trust and the NIHR Biomedical Research Centre: Exeter, and was presented at the American Society of Human Genetics annual meeting, according to University of Exeter and News-Medical reporting.
| Finding | Figure |
|---|---|
| Genomes analysed | Nearly 1 million |
| Variants per genome | About 5 million |
| Gene-altering variants | About 10,000 |
| Rare disease-causing variants per person | 1–3 |
| Conditions in polygenic analysis | 28 |
| High-risk conditions for most people | About 3 |
Conclusion
For readers, the takeaway is reassuring and practical: variation is the norm, not the exception. If a genetic test ever labels you “high risk”, ask what it means in your context — your symptoms, your family history, your health — before worrying. Genes load the dice; they do not roll them alone.
This article is educational, not medical advice. Consult a qualified clinician for individual decisions.
Read more on Watan News: Most people carry high genetic risk for three diseases — and that is normal.
