Spit Analysis Can Reveal Person's Age

There are certain compounds in a person's spit that can reveal their age to within 5 years. No kidding. There are certain things we know about DNA. We know that DNA gets methylated (like ornaments on a Christmas tree). We also know that the methylation pattern on the DNA changes with age. So the hypothesis was whether looking at the methylation pattern of the DNA can reveal a person's age? And guess what... it does according to a recently published study.

In this study published on PLoS ONE, researchers studied the saliva of identical twins to figure out what sites appeared to correlate best with age. They narrowed it down to 88 DNA methylation sites that seemed to correlate with age. Based on these 88 sites, they than verified it in 60 men and women, ages 18 to 70, and found that two genes in particular had the strongest age correlation to within 5 years. Amazing!

This finding can certainly help with crime-fighting, but also has potential for spit being a marker for all sorts of other biological problems that have yet to be discovered (perhaps even replace painful needle sticks for blood draws). After all, if a person's spit can reveal their age, who knows what else it can reveal about the person!

Reference:
Epigenetic Predictor of Age. PLoS ONE 6(6): e14821. doi:10.1371/journal.pone.0014821