History Main / DaddyDNATest

* Creator/PattyDuke had several lovers over the years, and a test was eventually done to determine the true father of her son Creator/SeanAstin. His father is Michael Tell, but her other lovers Desi Arnaz Jr., Creator/JohnAstin (who officially adopted him), and Michael Pierce all helped raise him.

There are cases where this would not help. If two or more identical siblings or clones are potential fathers to the child; having the same DNA, all of them will test positive for paternity if any of them does. Depending on how a sample is taken, someone with chimerism could test negative for paternity even if they were the father. These are very rare in real life, but [[TelevisuallyTransmittedDisease improbably common in fiction]].

The only case in which this would not help is if two or more identical siblings or clones are potential fathers to the child; having the same DNA, all of them will test positive for paternity if any of them does.

* On ''Website/NotAlwaysRelated'', [[https://notalwaysright.com/love-is-in-their-dna/237945/ a young man's flighty ex-girlfriend leaves him a child]], which his father assumes [[MamasBabyPapasMaybe is not actually his]]. Determined to prove it, he takes his "granddaughter" to get tested behind his son's back, starting a fight that drives them apart for months, then interrupts his own wife's birthday party with an "I TOLD YOU SO" cake and the unopened test results... '''which are positive for a match'''. The submitter describes him [[MyGodWhatHaveIDone dying a little inside]] upon reading it.

** [[https://www.youtube.com/watch?v=7GVsdg8_K-g Yuzuriha]] insists Kuroki to have a DNA test with his son to satisfy her suspicion about the boy's parentage. When the test reveals that Kuroki's son is not related to him, she {{faint|In Shock}}s.
** [[https://www.youtube.com/watch?v=seEHxvIgUOQ Akamatsu]] forces Karin to take a DNA test out of allegation of cheating. Unsurprisingly, the baby was Akamatsu's, but Karin still divorces him because of his stupidity and distrust.
** [[https://www.youtube.com/watch?v=cGgwS58aTtQ After Akane gave birth to her child]], Hiiragi insists that the baby was his, until his father requests a DNA test since there is a chance that the child is Kuroki's, who was Akane's previous husband. Hilariously, ''neither'' of the men are the child's father, but instead, it's Akamatsu.
** When [[https://www.youtube.com/watch?v=kXd1RoDSSgo Tachibana]] hears a rumor that Azami isn't his biological daughter, he does a DNA test on her and gets a zero percent match. It turns out that Akane cheated on him with Hiiragi.

** [[https://www.youtube.com/watch?v=bqomxb5wEq0 Azami]] claims to be Tachibana's illegitimate daughter, however Karin demands a DNA test to confirm her paternity. The result reveals [[spoiler: that Azami is not Tachibana's daughter, and she actually turns out to be Hiiragi's illegitimate daughter from his affair with another woman. It is revealed that Hiiragi actually tried to pin the blame on Tachibana about his affair by using his daughter to cover his tracks.]]

* ''Literature/TheInheritanceGames'': When Tobias Hawthorne leaves his fortune to Avery Grambs, people start speculating that she is his secret illegitimate child. A [=DNA=] test proves Avery is not a Hawthorne. However, when it turns out [[spoiler:Tobias' son Toby was adopted, Avery starts thinking that he may be her father, since it turns out that he had an affair with Avery's mother. He's not. A paternity proves that Ricky Grambs is her father after all.]]

* Interesting twist in ''ComicStrip/SafeHavens'': Samantha runs a genetic profile on her daughter Maria. She has no doubts at all about Maria's parentage, but she ''is'' a geneticist by profession so naturally she's curious about what's in her daughter's DNA. However, she keeps getting Maria's profile mixed up with the ''other'' Maria's-Maria the time traveler-because they're identical...and she freezes as the implications sink in.
--->'''Maria:''' [[spoiler: [[WhamLine Hi]] [[KidFromTheFuture Mom.]]]]

* ''ComicBook/SpiderMan'': In ''[[ComicBook/TheAmazingSpiderManJMichaelStraczynski Sins Past]]'', Peter ''knows'' he's not the father of twins Gabriel and Sarah Stacy but tests his blood sample with the twins blood sample to find out for sure. Justified, since he and Gwen haven't even slept together prior to the twins conception and this leads to him to discovering that Gwen cheated on him and Mary Jane confirming his worst.

* In a story arc in ''Franchise/{{Batman}}: Gotham Knights'' had the villain Bane discovering evidence suggesting that his real father was an American doctor, and, as the doctor has died, seeking a DNA matching test with the doctor's son -- Bruce Wayne.
* A variation in ''ComicBook/HelOnEarth'' When Franchise/{{Superman}} puts his battle-suit on ComicBook/{{Superboy}}, the [[ChestInsignia family crest]] should have changed the instant it identified his Kryptonian bloodline. It stayed the same, confirming Superman's suspicions that Superboy's his clone.

* On ''Series/TheRedGreenShow'', an old rich guy dies, and since he amassed his fortune by [[ADateWithRosiePalms donating to the local sperm bank]], everyone in town gets DNA tested hoping to get a match, and therefore be entitled to the inheritance. Shockingly, ''all'' of the DNA tests turn out to be exactly the same. Incestuous implications aside, this unfortunately only entitles everyone to a few bucks each since the inheritance has to be split so many ways. [[spoiler:It turns out that this was because [[StickyFingers Mike]] stole all the test tubes, so the testers had to use the lids off pickle jars, and simply ended up testing the chemical composition of pickle juice. The reason this matched the old guy's DNA was because [[TheAlcoholic he was always pickled himself]]]].

* ''Series/BostonLegal'': A man who was born out of artificial insemination was dating a woman who was born the same way and they were afraid of being [[BrotherSisterIncest half-siblings]]. To learn if they had the same father or not, they sued the lab to force them to tell because a DNA test using only the couple's blood would be inconclusive if they were half-siblings or complete strangers. (Whether this counts as a case of [[DanBrowned the writers failing to do the research]] or just [[ArtisticLicense "Because The Plot Demanded It"]], it's still scientifically incorrect: Half-siblings should be a roughly 25% genetic match, and as such, fairly easy for a DNA test to catch, particularly if they have DNA from either of their mothers.)