Is chronotype hereditary?
Explore the genetic variants associated with being a morning or evening person.
Chronotype describes when during the day your body naturally wants to sleep and wake. The internal circadian rhythm is driven by a genetic clockwork — and large studies have linked hundreds of loci to morningness or eveningness.
What the analysis shows
DNAHelper shows which chronotype-associated variants your raw file contains and what research has linked them to. The result is an association — not a verdict on when you should go to bed. The analysis is based on the traits chronotype measurement, circadian rhythm (934 associated variants, strong evidence strength).
Which variants matter
The internal clock is driven by a network of genes where BMAL1 (ARNTL) and the PER genes are central — they form the molecular oscillator in nearly all cells. Variants in and near these genes are linked to chronotype.
Beyond the clock genes there are signals in genes affecting sleep duration, retinal light sensitivity and hormone profiles across the day.
What research has actually found
GWAS with hundreds of thousands of participants have replicated hundreds of loci linked to self-reported chronotype. The link to the classic clock genes is robust, but each variant shifts the circadian rhythm only marginally.
Chronotype is also not static — the same person often drifts toward eveningness in the teens and toward morningness with age.
What matters more than genes
Light exposure — morning light versus evening light and screens in particular — is the strongest environmental lever on the circadian rhythm. Work hours, children and social routines often push chronotype in one direction.
Age is the single biggest factor: teenagers are almost always evening types, and most people become morning types with age — regardless of genetics.
What the result means — and does not mean
The analysis is based on the traits chronotype measurement, circadian rhythm (strong evidence strength). Associations are statistical — they describe populations, not destinies. Read how we grade evidence in our methodology.
Privacy: your file never leaves the browser
You pick your raw file locally — it is parsed and analysed entirely in your browser and is not uploaded for the standard analysis. The only exception is the optional DNA Chat feature where you, after explicit consent, can share selected variants. Read the privacy policy · What happens to your DNA file?
Compatible raw files
Works with raw data exports from MyHeritage, 23andMe, AncestryDNA and FamilyTreeDNA (.txt, .csv, .zip). The download guides show exactly where to find the file at your provider — and the file formats are explained here.
Also read: Method & science · All analyses · All traits · Sleep and circadian rhythm