Monthly/yearly subscription to updates of some sort
And tie it into credit score fear.
"Do you want a higher credit score? Sure, we all do. So be sure your 23andMe DNA is up-to-date!"
Frankly, I think these mail-in DNA tests are like modern-day phrenology, but you could spin in that "pay us $x per year, and we will analyze your DNA every month once research becomes available".
Monthly/yearly subscription to updates of some sort