Been doing that for years, a fan of the "spit method" lol. I always leave my DNA on everything I do, if not blood, spit, a little rub in my hair with a needle to make it slide better, licking the thread (also the eye of the needle will thread easier if it is wet). My kids say I don't need a label, in 100 years they will just scan for DNA and mine will be readily identifiable!