Figure 3
Perinatal iron exposure and genome-wide cord blood DNA methylation. (a) No genome-wide significant association between maternal iron supplement use in pregnancy and genome-wide DNA methylation assayed by Illumina 450 K chip, in n = 1,062 mother/child-pairs in the MoBa cohort. (b) Methylation in cord blood samples from the MoBa cohort by the coding SNP rs1800562 (p.C282Y) in the HFE gene at chromosome 6. (c) Methylation in cord blood samples from the MoBa cohort by the coding SNP rs1799945 (p.H63D) in the HFE gene at chromosome 6. (d) Fetal HFE rs1800562 genotype and genome-wide cord blood DNA methylation in n = 1,062 children in the MoBa cohort showed multiple differentially methylated sites near the HFE gene with genome-wide significance. rs1800562 is the hemochromatosis associated non-synonymous p.C282Y SNP. The red marks represent associations for the six methylation sites (CpGs) that were replicated in the ALSPAC cohort in the UK, for the same SNP, reported in their metQTL database16. The Manhattan plot is split according to direction of association, with positive associations (hypermethylation) associated with the p.C282Y variant) at the top and negative associations (hypomethylation) at the bottom. The mid panel indicates the position of the genes in this region of chromosome six. Numbers on the x-axis indicate genome position.
