Age of a person can now be determined from his/her saliva. It may have widespread application including in forensic science.
Your spit reveals your age, scientists say
Scientists have discovered that the way the DNA in your spit changes over time reveals your age to within five years.
As we get older, our DNA gets methylated, meaning that certain genes are told to turn on or off based on our lifestyle and environmental factors, such as how we eat or the toxins to which we’re exposed.
the sequence of the genes themselves is not modified, but their expression is. What we found is that the degree of methylation at a small number of places in the human genome is linked to our age. The correlation is high enough that we can predict what the age of a person is by just having access to a sample of their saliva.
The researchers, who published their results in PLoS ONE on June 22nd, are now looking at the minority of the population in which methylation does not correlate with their actual age. This discrepancy could lead to scientists one day calculating a person’s “bio-age” — or their biological age — as opposed to their chronological age.