Fig. 1

Schematic diagram for the season of birth-DNA methylation (DNAm) analyses. Numbers included in the analyses are indicated. PACE Pregnancy And Childhood Epigenetics, EWAS Epigenome Wide Association Study, DMP Differentially Methylated Probe, FDR False Positive Rate, DMR Differentially Methylated Region. EWASs and meta-analysis were carried out on at-birth and childhood samples separately. All participating cohorts were from the northern hemisphere (range 37.2–71.2°N). Latitude ≥ 50°N represents a subset of cohorts from 50 to 71.2°N (referred to as “higher latitude subgroup” in the text). Latitude < 50°N is a subset of cohorts from 32.7 to 50°N (referred to as “lower latitude subgroup” in the text. ^a27 independent cohorts, but a total of 33 datasets as 6 cohorts contributed to both at-birth and childhood analyses. ^bAt-birth blood samples (cord and heel prick). ^cWhole blood samples (age 1–11 years). ^dThis analysis was not done due to its small sample size