Research Paper Volume 8, Issue 5 pp 1034—1044

Epigenetic age predictions based on buccal swabs are more precise in combination with cell type-specific DNA methylation signatures


Figure 3. Smoking, ethnicity and gender do not impact on DNAm at selected CpG sites. (A) DNAm levels at the three age-associated CpG sites (ITGA2B, ASPA, and PDE4C), and the two cell type associated CpGs (CD6 and SERPINB5) did not differ in blood samples of current smokers (red) and never-smokers (blue; GSE50660). In contrast, such differences were validated in three CpG sites, which have previously been described as smoking-associated. (B) DNAm profiles of pure nasal epithelial cells of smokers (red) and non-smokers (blue) did not demonstrate differences in the two cell type associated CpGs (GSE28368). (C) Pyrosequencing analysis of the Buccal-Cell-Signature in 36 samples with known smoking status did not reveal differences in the cellular composition of buccal swabs. (D) DNAm profiles of children (1 to 17 years) did not reveal significant differences between different ethnic groups (GSE36054; blue: black donor; red: white donor; black lines: Asian donor). (E) None of the five CpGs revealed gender-associated differences (GSE40279; blood samples of 40 to 50 year old donors; blue: female; red: male). * P < 0.05; *** P < 0.0005; Whiskers indicate 10% and 90% percentiles, respectively.