History Main / WrongGeneticSex

* [[spoiler:Kyoko]], the protagonist of one of the arcs of ''Manga/LevelE'', is found to be one, Unfortunately, that might spell the end of Mankind (long story).

** Cal also meets a woman with [[http://en.wikipedia.org/wiki/Androgen_insensitive Androgen insensitivity syndrome]], an intersex condition that causes the woman affected to be born with a vagina, but with XY chromosomes, no uterus, and internal testes where the ovaries would typically be. Despite being able pass as a woman, she strongly identifies herself as a {{hermaphrodite}} and is an intersex rights activist.
* The original incarnation of Sadako of ''Literature/TheRing'' was this. In the book, a doctor was the guy who threw her into the well, because he found out.

* In one episode of ''Series/{{House}}'', a woman turns out to be suffering from testicular cancer, due to a [[http://en.wikipedia.org/wiki/Androgen_insensitive surprisingly common medical condition]] that causes some people with XY chromosomes to develop into infertile women with internal testicles instead of ovaries[[note]]In reality, androgen-insensitive women seldom have a significantly increased risk of testicular cancer; rather the "threat" of cancer is used as an excuse to remove the gender-incongruous gonads despite their being fundamentally harmless[[/note]].

* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes an androgen reaction that makes the gonads instead become testes and the Fallopian tubes wither away whilst retaining the vas deferens. [[http://en.wikipedia.org/wiki/Androgen_insensitive Androgen insensitivity syndrome]], is an intersex condition that causes the woman affected to be born with a vagina, but with XY chromosomes, no uterus, and internal testes where the ovaries would typically be. These women overwhelmingly identify as female and heterosexual.

Most people who have passed grade school know that men have one X and one Y chromosome while women have two X chromosomes. However, in RealLife it's not always that simple.

The whole issue of gender identity aside, anything that interferes with fetal development can cause various degrees of feminization or masculinization ranging from people who are genetically XY and physically female to people who are genetically XX and physically male to people who are intersex and whose anatomical sex is neither male nor female. There is also a phenomenon called ''[[http://en.wikipedia.org/wiki/Chimera_(genetics) chimerism]]'' which can cause different parts of the body to have different DNA, meaning DNA from someone's blood or saliva (the most common sources for DNA tests) may not match DNA from other parts of their bodies, which for fictional purposes usually means hair, skin or semen.

In fiction, this usually pops up in various kinds of detective stories and is used as a excuse to make a DNA test into a RedHerring. It can also be a source of drama or simply a character quirk. The actual cause is likely to be HandWaved or just glossed over. {{Transsexual}}s are covered by their own trope but may also fall under Wrong Genetic Sex if their transgender status is not known in advance and the plot hinges on the difference between their chromosomes and their appearance. Intersex people may also be included under similar circumstances. However, only individuals count: If an entire population is intersex, then it's a OneGenderRace.

See also {{Hermaphrodite}}, which may overlap but is in many cases a distinct phenomenon. Both "hermaphrodite" and "pseudohermaphrodite" were used as medical terms for these conditions in the past but that usage was not strictly accurate and is now considered pejorative.

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!!Examples

[[AC:{{Anime}} & {{Manga}}]]
* In ''Manga/TheDayOfRevolution'', the supposedly male protagonist discovers in the first chapter that he is intersexed and genetically female. Despite some misgivings and with a push from her parents she decides to reinvent herself as a girl. HilarityEnsues.
* In ''Anime/EarthMaidenArjuna'', one of the female ecology activists has this as a result of medication her mother took while pregnant.
* [[spoiler:Kyoko]], the protagonist of one of the arcs of ''Manga/LevelE'', is found to be one, Unfortunately, that might spell the end of Mankind (long story).

[[AC:{{Literature}}]]
* The protagonist from Creator/RobertAHeinlein's ''Literature/AllYouZombies'', who starts out as an intersex female and...it gets complicated. Her actual degree of intersexualization approaches true [[{{Hermaphrodite}} hermaphrodism]] and wouldn't be biologically possible, except [[spoiler:there's no logical reason why she'd be human anyway]].
* Calliope (later Cal) from the book ''Literature/{{Middlesex}}'' was born intersex (genetically XY) and raised female until the age of fourteen. Notably, her being RaisedAsTheOppositeGender was completely unintentional on the part of both her doctors and her parents, since the doctor was nearsighted and had no idea that she was actually male.
** Cal also meets a woman with [[http://en.wikipedia.org/wiki/Androgen_insensitive Androgen insensitivity syndrome]], an intersex condition that causes the woman affected to be born with a vagina, but with XY chromosomes, no uterus, and internal testes where the ovaries would typically be. Despite being able pass as a woman, she strongly identifies herself as a {{hermaphrodite}} and is an intersex rights activist.
* The original incarnation of Sadako of ''Literature/TheRing'' was this. In the book, a doctor was the guy who threw her into the well, because he found out.

[[AC:LiveActionTV]]
* In one episode of ''Series/LawAndOrderSpecialVictimsUnit'', the episode starts with a rapist getting killed by his victim and the DNA evidence leads the detectives to a teenage boy who just happens to have an ironclad alibi. It turns out his twin "sister" is actually his twin ''brother''; it seems he lost his penis when they were circumcised as babies and the doctors who botched the operation covered their tracks by completing the job and talking his parents into raising him as a girl.
** Sadly, this is actually TruthInTelevision: The episode is based on an actual case. Just like the character in the episode, the [[http://en.wikipedia.org/wiki/David_Reimer real man]] vehemently reverted to a male gender identity as soon as he got the chance. Sadly, he ended up killing himself [[spoiler: instead of killing [[http://en.wikipedia.org/wiki/John_Money the doctor]] like his fictional counterpart in SVU did]].
* In one episode of ''Series/{{House}}'', a woman turns out to be suffering from testicular cancer, due to a [[http://en.wikipedia.org/wiki/Androgen_insensitive surprisingly common medical condition]] that causes some people with XY chromosomes to develop into infertile women with internal testicles instead of ovaries[[note]]In reality, androgen-insensitive women seldom have a significantly increased risk of testicular cancer; rather the "threat" of cancer is used as an excuse to remove the gender-incongruous gonads despite their being fundamentally harmless[[/note]].
* This is a major plot point in an episode of ''FreaksAndGeeks'', when Ken's new girlfriend Amy tells her she's one of these. There was no DNA test or anything - the conflict came from Amy getting upset at Ken (who initially struggled with the revelation) telling his friends her big secret.
* In one episode of ''Series/{{CSI}}'', a DNA sample with female chromosomes turned out to belong to a male character. He was a post-operation trans man and it wasn't known that he had been born female-bodied.
* In one episode of ''Anna & Kristina's Grocery Bag'', Anna and Kristina couldn't figure out which part of their lobsters was the coral, which part was the roe and which were the "intestine-y bit(s) one should not eat" and Kristina asked if lobsters were hermaphrodite-both [male and female]. As it turns out, they needed female lobsters for their recipe but the cookbook they were testing did not divulge that detail.
* In one episode of ''Series/WhoseLineIsItAnyway'', during a game of Party Quirks, Colin was playing a character who suspected that people were not the gender they purported themselves to be and he spent his time during the game [[http://www.youtube.com/watch?v=QAjTtNALURg feeling up his fellow contestants.]]

[[AC:RealLife]]
* Chimerism has been found to be the cause of rare—sometimes, seemingly impossible—coat colors in several species of animal, including dogs, cats, and horses. One particular horse appeared to be a stallion, but was found to have a blend of stallion and mare DNA; calico tomcats are the feline equivalent.
* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes an androgen reaction that makes the gonads instead become testes and the Fallopian tubes wither away whilst retaining the vas deferens. [[http://en.wikipedia.org/wiki/Androgen_insensitive Androgen insensitivity syndrome]], is an intersex condition that causes the woman affected to be born with a vagina, but with XY chromosomes, no uterus, and internal testes where the ovaries would typically be. These women overwhelmingly identify as female and heterosexual.
* The "switch" for a fetus developing as a male is primarily controlled by just ''a single gene'' on the Y chromosome. The SRY gene is so crucial that a mutation on just this one gene can cause an XY female, and its translocation to an X chromosome can cause an XX male.
* [[http://en.wikipedia.org/wiki/XX_male_syndrome XX male syndrome]] is a rare intersex condition that causes the male affected to have XX chromosones, as well as small testes, varying degrees of [[http://en.wikipedia.org/wiki/Gynecomastia gynecomastia]], poor facial hair growth, and diminished libido. Men and boys with the condition are otherwise not particularly feminine.
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* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes an androgen reaction that makes the gonads instead become testes and the Fallopian tubes wither away whilst retaining the vas deferens. Androgen insensitivity syndrome will cause a chromosomal male to instead develop female genitalia (sans ovaries).

** Cal also meets a woman with [[http://en.wikipedia.org/wiki/Androgen_insensitive Androgen insensitivity syndrome]], which basically means she's genetically male with the body of an infertile female. Despite being able to come across as a woman, she strongly identifies herself as a {{hermaphrodite}} and is an intersex rights activist.

* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes a hormones reaction that makes the gonads instead become testes and the Fallopian tubes wither away whilst retaining the vas deferens. Androgen insensitivity syndrome will cause a chromosomal male to instead develop female genitalia (sans ovaries).

* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes the gonads to instead become testes and the Fallopian tubes to wither away whilst retaining the vas deferens. Androgen insensitivity syndrome will cause a chromosomal male to instead develop female genitalia (sans ovaries).

* In human beings and most types of animals all embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but usually the presence of a Y chromosome causes the gonads to instead become testes and the Fallopian tubes to wither away whilst retaining the vas deferens. Androgen insensitivity syndrome will cause a chromosomal male person to have female genitalia (sans ovaries).

* The human body is physically female by "default" during the very early stages of development, and what turns that female body into a male body is the action of testosterone in the womb; however, there's a rare condition called Androgen Insensitivity Syndrome in which a resistance to testosterone causes a person with one X chromosome and one Y chromosome develop as a female (although sterile).
** It is a common misconception that all embryos start out as female. All embryos begin with undifferentiated gonads connected to both ductus (vas) deferns and oviducts (Fallopian tubes). By default the gonads will develop into ovaries and the vas deferens will disappear, but the SRY causes the gonads to instead become testes and the Fallopian tubes to wither away whilst retaining the vas deferens. Still, androgen insensitivity syndrome will cause a person to have female genitalia (sans ovaries).

* In one episode of ''Series/{{House}}'', a woman turns out to be suffering from testicular cancer, due to a [[http://en.wikipedia.org/wiki/Androgen_insensitive surprisingly common medical condition]] that causes some people with XY chromosomes to develop into infertile women with internal testicles instead of ovaries.
** It should be noted that in reality, androgen-insensitive women seldom have a significantly increased risk of testicular cancer; rather the "threat" of cancer is used as an excuse to remove the gender-incongruous gonads despite their being fundamentally harmless.

* The human body is physically female by "default" during the very early stages of development; and what turns that female body into a male body is the action of testosterone in the womb, however, there's a rare condition called Androgen Insensitivity Syndrome in which a resistance to testosterone causes a person with one X chromosome and one Y chromosome develop as a female (although sterile).

* Calliope (later Cal) from the book ''{{Middlesex}}'' was born intersex (genetically XY) and raised female until the age of fourteen. Notably, her being RaisedAsTheOppositeGender was completely unintentional on the part of both her doctors and her parents, since the doctor was nearsighted and had no idea that she was actually male.

* This is a major plot point in an episode of ''FreaksAndGeeks'', when Ken's new girlfriend Amy tells her she's one of these. There was no DNA test or anything - the conflict came from Amy getting upset at Ken telling his friends her big secret.

** Sadly, this is actually TruthInTelevision: The episode is based on an actual case. Just like the character in the episode, the [[http://en.wikipedia.org/wiki/David_Reimer real man]] vehemently reverted to a male gender identity as soon as he got the chance. Sadly, the real man ended up killing himself [[spoiler: instead of killing [[http://en.wikipedia.org/wiki/John_Money the doctor]] like his fictional counterpart in SVU did]].
* In one episode of ''Series/{{House}}'', a woman turns out to be suffering from testicular cancer, due to a [[http://en.wikipedia.org/wiki/Androgen_insensitive surprisingly common medical condition]] (especially [[http://www.secondtype.info/ais.htm among supermodels]]) that causes some people with XY chromosomes to develop into infertile women with internal testicles instead of ovaries.

* Chimerism has been found to be the cause of rare—sometimes, seemingly impossible—coat colors in several species of animal, including dogs, cats, and horses. One particular horse appeared to be a stallion, but was found to have a blend of stallion and mare DNA; many calico tomcats are the feline equivalent.

* The original incarnation of Sadako of ''TheRing'' was this. In the book, a doctor was the guy who threw her into the well, because he found out.

* In ''Anime/EarthMaidenArjuna'', one of the female ecology activists has this, with the implication that it was the result of the polluted environment.

* Calliope (later Cal) from the book ''{{Middlesex}}'' was born intersex (genetically XY) and raised female until the age of fourteen.

* Kyoko, the protagonist of one of the arcs of ''Manga/LevelE'', is found to be one, Unfortunately, that might spell the end of Mankind (long story).

See also {{Hermaphrodite}}, which may overlap but is in many cases a distinct phenomenon. Both "hermaphrodite" and "pseudohermaphrodite" were used as medical terms for these conditions in the past but that usage was not strictly accurate and is now considered perjorative.

* The protagonist from Creator/RobertAHeinlein's ''Literature/AllYouZombies'', who starts out as an intersex female and...it gets complicated. Her actual degree of intersexualization approaches true [[{{Hermaphrodite}} hermaphrodism]] and isn't biologically possible.

* In ''TheDayOfRevolution'', the supposedly male protagonist discovers in the first chapter that he is intersexed and genetically female. Despite some misgivings and with a push from her parents she decides to reinvent herself as a girl. HilarityEnsues.
* In ''EarthMaidenArjuna'', one of the female ecology activists has this, with the implication that it was the result of the polluted environment.
* Kyoko, the protagonist of one of the arcs of ''LevelE'', is found to be one, Unfortunately, that might spell the end of Mankind (long story).

* The original [[TheRing incarnation of Sadako]] was this. In the book, a doctor was the guy who threw her into the well, because he found out.

* In one episode of ''LawAndOrderSpecialVictimsUnit'', the episode starts with a rapist getting killed by his victim and the DNA evidence leads the detectives to a teenage boy who just happens to have an ironclad alibi. It turns out his twin "sister" is actually his twin ''brother''; it seems he lost his penis when they were circumcised as babies and the doctors who botched the operation covered their tracks by completing the job and talking his parents into raising him as a girl.

* In one episode of ''[[CrimeSceneInvestigation CSI]]'', a DNA sample with female chromosomes turned out to belong to a male character. He was a post-operation trans man and it wasn't known that he had been born female-bodied.

* In one episode of ''Whose Line Is It Anyway?'', during a game of Party Quirks, Colin was playing a character who suspected that people were not the gender they purported themselves to be and he spent his time during the game [[http://www.youtube.com/watch?v=QAjTtNALURg feeling up his fellow contestants.]]

* The protagonist from Creator/RobertAHeinlein's ''AllYouZombies'', who starts out as an intersex female and...it gets complicated. Her actual degree of intersexualization approaches true [[{{Hermaphrodite}} hermaphrodism]] and isn't biologically possible.

* The protagonist from RobertHeinlein's ''AllYouZombies'', who starts out as an intersex female and...it gets complicated. Her actual degree of intersexualization approaches true [[{{Hermaphrodite}} hermaphrodism]] and isn't biologically possible.

* Chimerism has been found to be the cause of rare, seemingly impossible coat colors in both dogs and horses; one noted example appeared to be a stallion but was found to have a blend of stallion and mare DNA.

* The original [[{{Ring}} incarnation of Sadako]] was this. In the book, a doctor was the guy who threw her into the well, because he found out.