Fig. 2
Preterm births (PTB) were associated with global alterations in infants’ cord blood DNA methylation. a Manhattan plot and b volcano plot illustrating the relationship of the 85,624 infant cord blood CpGs analyzed with respect to PTB. The top 10 CpGs with the smallest P values are indicated on both plots and labeled with the gene it is associated with or CpG identifier if the CpG lies within an intergenic region. Points on each plot represent individual CpGs which in a have genomic locations on the horizontal axis with alternating colors representing different chromosomes and in b have the change in DNA methylation Z-score on the horizontal axis. The red horizontal line in a represents the Bonferroni threshold (P < 5.8 × 10−7). Two hundred ninety-six infant cord blood CpGs were found to significantly associate with PTB and are indicated as red points in b. In both plots, the vertical axis represents the negative log10 P values with respect to preterm birth status, adjusted for infant sex, ethnicity, cell-type proportions, and bisulfite conversion batch