New saliva test is accurate biological age predictor

Spitting distance – Deep Longevity’s straightforward saliva test can predict biological age with 4.7 years accuracy.

Endurance RP’s wholly-owned subsidiary Deep Longevity, Inc, a leading provider of deep biomarkers of aging and longevity is pleased to announce the publication of its Frontiers in Aging article “Adapting blood DNAm aging clocks for use in saliva samples with cell-type deconvolution”.

Longevity.Technology: Blood is the most popular human tissue used for clinical analysis. It is a liquid tissue that permeates all other organs and thus reflects the state of the whole organism. Blood is also preferred by most biogerontologists, who study the aging process and its footprints. However, drawing blood is a painful procedure that requires an appointment with a clinic – something many consumers are either unwilling to do, or don’t have the time for. Saliva is a much easier tissue to collect, as it can be done at home and non-invasively.

Last year Deep Longevity released an accurate epigenetic aging clock – DeepMAge. It uses the information about DNA modification to estimate a person’s pace of aging, which has been shown to be associated with cancer, dementia and irritable bowel disease. However, DeepMAge could only be used with blood samples, which limited the range of its use.

The Frontiers publication demonstrates how the same blood-trained model can be repurposed for saliva samples with practically no drop in performance. Originally, DeepMAge could predict human age with 20.9 years of error when used on saliva, but the new adjustment restored its accuracy to 4.7 years.

The adjustment makes use of the inherent heterogeneity of saliva samples that consist of variable proportions of epithelial and immune cells. These cell types age at a different speed, and when they are mixed the organismal pace of aging is obfuscated. Cell-type deconvolution method EpiDISH allows obtaining the composition of a saliva sample with no additional information needed. Combining this method with a blood aging clock salvages its performance.

Now, DeepMAge and other blood-trained aging clocks can be easily applied to saliva, which enables a variety of consumer-friendly applications of the biogerontological models.
As personalised medicine develops, there is demand for data that can be gathered often and easily; UK start-up AgeCurve can generate deep age profiles by sequencing and quantifying thousands of human proteins to assess different aspects of the ongoing biological aging process – and all from a saliva sample. DNA and epigenomes can be easily sequenced from saliva tests, leading to interest from the insurance industry.

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