Yes. Get a blood transfusion from a native American. It takes the body 90 days to shed blood cells that are not a genetic match to the host. A blood sample can be used to cheat DNA testing. Now hair or skin cells are another story.
It’s why they do cheek and saliva samples...because blood could be done this way....also mature red cells have no nucleus, only immature “nucleated ones” would have any dna but they aren’t normally seen in large numbers unless the body is stressed because of bleeding. Also mixes of 2 sets of complete dna sequences in one sample would flag as a suspicious anomaly.