The following script demonstrates the work conducted for the manuscript "Pediatric Buccal Epithelial Cell Proportions Decrease With Age From Infancy through Childhood: Considerations for PedBE in Pediatric Research"

Following is the abstract-

Children’s cheek swabs, cellularly heterogeneous samples consisting primarily of buccal epithelial cells (BECs), are widely used in epigenetic association studies of pediatric DNA methylation and biomarker creation, e.g., the Pediatric Buccal Epigenetic (PedBE) clock. Although BEC proportion is suggested to decrease with age, this was not investigated during childhood. Here, we analyzed cheek swabs from 4626 typically developing children 2-months to 20-years-old. Estimated BEC proportion declined from infancy to childhood inversely with both increasing chronological and predicted epigenetic age. However, estimated BEC did not associate with age from pre-adolescence through late adolescence. Variability in estimated BEC proportions continually increased with chronological age through the entire pediatric range. These trends held inversely true for estimated neutrophil proportions. Although estimated BEC proportion was weakly related to epigenetic age acceleration (EAA), this was attenuated to non-significance after correcting for BECs during initial EAA estimation. Notably, correcting for BEC proportion attenuated the association of PedBE EAA with obsessive-compulsive disorder and strengthened the association with diurnal cortisol slope. Thus, the change in children’s oral cell proportions with age is a crucial consideration for cell type-sensitive research.