Research

Mixed

Genetic variants associated with excessive daytime sleepiness cluster into two distinct biological subtypes: 'sleep propensity' (linked to higher sleep efficiency and morning chronotype) and 'sleep fragmentation' (linked to lower sleep efficiency and insomnia symptoms).

If you struggle with daytime sleepiness, recognize that your experience may stem from one of two genetic predispositions: high sleep drive (propensity) or poor sleep continuity (fragmentation). Those with high propensity may benefit from circadian alignment (morning light), while those with fragmentation may need to address sleep quality or underlying disorders like apnea, rather than just increasing total sleep time.

GoodQualifiesHIGH confidence
The 42 sleepiness variants primarily cluster into two predominant composite biological subtypes - sleep propensity and sleep fragmentation.
Heming Wang et al. · Nature Communications · 2019

Why this rating

Large sample size (N=452,071) and replication in independent cohorts, though based on self-reported data.

Source

Genome-wide association analysis of self-reported daytime sleepiness identifies 42 loci that suggest biological subtypes

Heming Wang et al. · Nature Communications · 2019

DOI 10.1038/s41467-019-11456-7

cohort · n=452071Cited 251×
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DOI resolved against Crossref · corpus check 2026-06-10

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