This holiday season, more people than ever before are giving the gift of spit. Well, what’s in your spit, to be precise. Want to know where your ancestors once walked or whether you’re at risk for a genetic disease? There’s a spit tube kit for that. And customers are buying them in record numbers. Between Black Friday and Cyber Monday, leading personal genomics company AncestryDNA sold about 1.

Learn about your ad choices: dovetail.prx.org/ad-choices