Thanks to the innovative and ever-developing technology of the modern age, learning about where you came from is as easy as spitting in a cup.

Genetic tests revealing your ancestry and personal health-related information, such as the “23andMe” DNA test, are just a click away for consumers interested in examining their lineage — no health care professional needed. That’s why a lot people take them just for fun. But as described in these 12 testing stories, a person’s results can reveal seriously uncomfortable truths they never expected to face.

1. “My mom did 23 and Me this summer, it came back saying my uncle was only a half uncle. She asked family friends and it turns out my grandmother had an affair and passed my mom off as her father’s kid — a fact that my grandmother clearly intended to take to her grave but science caught up.” — reverendexile

2. “In my genetics class we do a blood typing lab and our teacher told a story about her first year doing it where there was a girl who had a blood type that meant her dad couldn’t be her actual father and the mom (who also worked at the school) got caught cheating.” — Xzeener

3. “A former coworker of mine took the test and found she had a different father than her sister and neither were related to their father. She decided to confront her mom about her infidelity. She found out that her mom and dad were into group sex and that the biological fathers could be a number of gentlemen.” — MTGothmog

4. “So I did Ancestry. My father is ‘an eighth Cherokee’ and my mother ‘a little.’ They insist they’re ‘on the rolls’ somewhere. Ancestry came back 0% Native American. They’re not sure which is worse- did I get switched at the hospital or is their Cherokee heritage a lie?” — JustGreenGuy7

5. “This is how my ‘brother’ found out my father wasn’t his father. I’m adopted and last year found my biological father and mother. One of my new brothers also took the test and we did not match, although I DID match with our father…and he did not. Found out mom had had an affair while father was in Korea during the war. Oops!” — Edrondol

6. “My girlfriend got us tests for Christmas, and ever since posting about it on Facebook my mom has been sending her messages asking her to tell her the results before anyone else, including me.” — YoureRude

7. “At Christmas my grandma told me her friend took a test and found out her dad was her mom’s OBGYN.” — parksy555

8. “My wife had been told she was of Native American decent her entire life. Supposedly, her great grandmother was full-blood Native. This is a story her family still preaches to be true. Well, my wife does the DNA test only to discover it matches 100% with folks in Europe. Not a drop of Native American in her.” — pyledrive

9. “Through my DNA test, we discovered that my father has an older half brother that we never knew about before. He was adopted and trying to find his biological family. Turns out my grandpa had a little thing on the side. Both he and my grandmother have passed away… We don’t know if either of them were aware of the child (now grown up).” — dmc5

10. “My very French Canadian aunt (related to me by marriage) and her sister both took the test. My aunt’s result was more or less exactly what she expected. Her sister found out that she was 50% Arabic, not French at all. Looks like momma had some explaining to do.” — thepragmaticsanction

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Investigation Puts Ancestry DNA Kits To The Test Among Sets Of Triplets

Millions of people are purchasing and using home DNA kits to determine their ancestry. Inside Edition enlisted the help of two sets triplets and a set of quadruplets to investigate the accuracy of the at-home tests. Their ancestry should be absolutely identical since they all came from the same egg. Unfortunately, the reveal confused and disappointed the sisters because of the varied results. The set of quadruplets were almost identical and did not have the variations seen in the triplets.