Age-associated DNA-methylation changes can not only be tracked in the DNA of blood - but also in buccal swabs. Using a broad range of DNA-methylation profiles we elaborated an Epigenetic-Aging-Signature based on three specific CpG sites in the genome. For buccal swabs, it is important to adjust the mathematical models. Furthermore, the precision can be further enhanced by a "Buccal-Cell-Signature", which determines the percentage of buccal epithelial cells versus leukocytes.
Non-invasive harvesting of DNA
DNA can be harvested non-invasively from cells at the inside of a person´s cheek using buccal swabs – but these specimens resemble heterogeneous mixtures of buccal epithelial cells and leukocytes. The percentages of leukocytes vary between 5% - 60% in buccal swabs and 16% - 95% in mouthwash samples (saliva), the rest largely consists of buccal epithelial cells.
The epigenetic patterns differ significantly between different cell types. Therefore, epigenetic age predictions based on buccal swabs become more precise by integrating additional information on cell-type specific DNA methylation. Using multiple genome-wide datasets we have identified two genomic regions that are specifically methylated either in buccal epithelial cells or in leukocytes. Such analysis improves the precision of age-predictions with buccal swabs. However, the precision is still slightly higher with blood.
Area of application
Cygenia will analyze the DNA-methylation patterns at three or five specific genomic regions and thereby estimate donor age. In comparison to the “real” chronological age it is then possible to identify threats that affect epigenetic aging. This epigenetic aging signature is for buccal swabs and offers a convenient and non-invasive method for DNA-collection. It is not a medical device and not intended to screen, diagnose, treat, cure, or prevent any disease or condition or assess the risk of any disease or condition. Unless advised by any healthcare professional, biological age should not be used to determine or alter any chronological age-related health or medical treatments.
We can send you buccal swabs to use for sample collection that can be easily shipped by mail. Cygenia will then perform DNA isolation. Alternatively, you can already send genomic DNA.
Relevant Literature
Han et al. New targeted approaches for epigenetic age predictions. BMC Biology 2020.
Eipel M, et al. Epigenetic age predictions based on buccal swabs are more precise in combination with cell type-specific DNA methylation signatures. Aging 2016.
Weidner C.I. et al. Aging of blood can be tracked by DNA methylation changes at just three CpG sites. Genome Biology, 2014.
Patent applications:
DE 10 2016 109 291.6 (Buccal-Cell-Signature)
2012; EP12185698.3 (Epigenetic-Aging-Signature)