Figure 1

Cluster dendrogram based on all autosomal Infinium probes distinguishes placentas of different gestational age. Dendrogram showing the relationship between placental samples from three gestational ages based on DNA methylation levels (β-values) of all analysable Infinium probes. All samples clustered within their gestational age group, with no overlap between gestations, suggesting there are consistent genome-scale DNA methylation patterns associated with each gestational age. First trimester samples clustered away from second and third trimester samples, indicating that overall Infinium methylation patterns are more similar in second and third trimester compared to first trimester.