A post from Nature's own account is doing the rounds: a meta-analysis of more than a million people found over 1,000 genetic variants linked to personality. It is accurate, and the study is genuinely impressive. But the most useful number in it is not the 1,000 variants. It is how little of your personality those variants explain, and what that says about every DNA report that claims to read your character.
The Study
Schwaba and colleagues (Nature, September 2026) pooled 46 cohorts, between 611,000 and 1.14 million participants depending on the trait, to run genome-wide association studies of the Big Five: extraversion, agreeableness, conscientiousness, neuroticism and openness to experience. They found 1,260 lead variants, 824 of them new. The number of known genetic loci jumped from 4 to 39 for agreeableness, from 8 to 126 for openness, from 14 to 258 for extraversion and from 224 to 706 for neuroticism.
The Number That Matters
Add up the effect of all common variants, and they explain between 4.8% (agreeableness) and 9.3% (extraversion) of the differences between people on each trait. Even after correcting for the imperfect reliability of personality questionnaires, that rises only to 9.3 to 13.3%. Roughly nine-tenths of what makes you more or less extraverted, anxious or conscientious than the next person is not captured by the common DNA variants a genotyping chip can read.
Two more details are worth knowing. The five traits are genetically fairly distinct: 82% of the loci were tied to a single trait, and the average genetic correlation between traits was just 0.19. And by comparing siblings within families, the authors showed the associations are minimally distorted by shared family environment, so these small percentages are real signal, not an artefact.
What It Does Not Mean
It does not mean genes are irrelevant. Twin studies put personality heritability much higher; the gap is the "missing heritability" of rare variants and interactions that this kind of study cannot see. And the traits do matter: using Mendelian randomization, the authors found plausibly causal links from conscientiousness to lower body weight, less smoking and fewer hospital stays, and from neuroticism to a lower healthy-ageing score. Personality shapes lives. DNA chips just do not read personality very well.
What This Means for Your Raw DNA File
If a service takes your 23andMe or AncestryDNA data and returns a "personality type", a "leadership profile" or an "emotional resilience score", this study is the ceiling on what that can be worth: a signal explaining a single-digit share of the trait, built from associations discovered at the population level. It is the same limit we have described for DNA-based nutrient recommendations and for consumer tests claiming to detect ADHD genes. A well-built questionnaire measures your actual behaviour; a genotype estimates a weak predisposition. For personality, the questionnaire wins by a wide margin.
If you want to understand a trait that actually shapes your daily experience, start there: our free High Sensitivity (HSP) test measures sensory-processing sensitivity, a temperament trait with real research behind it, in about five minutes.