Are some children genetically predisposed to poor sleep? A polygenic risk study in the general population

Background Twin studies show moderate heritability of sleep traits: 40% for insomnia symptoms and 46% for sleep duration. Genome‐wide association studies (GWAS) have identified genetic variants involved in insomnia and sleep duration in adults, but it is unknown whether these variants affect sleep during early development. We assessed whether polygenic risk scores for insomnia (PRS‐I) and sleep duration (PRS‐SD) affect sleep throughout early childhood to adolescence. Methods We included 2,458 children of European ancestry (51% girls). Insomnia‐related items of the Child Behavior Checklist were reported by mothers at child's age 1.5, 3, and 6 years. At 10–15 years, the Sleep Disturbance Scale for Children and actigraphy were assessed in a subsample (N = 975). Standardized PRS‐I and PRS‐SD (higher scores indicate genetic susceptibility for insomnia and longer sleep duration, respectively) were computed at multiple p‐value thresholds based on largest GWAS to date. Results Children with higher PRS‐I had more insomnia‐related sleep problems between 1.5 and 15 years (BPRS‐I