Talk:Virilization
This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||
|
Untitled
editI see defeminization is on the list of sexology topics yet to be written. I think it would be a good idea to clearly contrast the ontogenetic processess of masculinization and defeminization in either this entry or in sexual differentiation --Pete.Hurd See talk:sexual differentiation. alteripse 8 July 2005 11:58 (UTC)
feminization
editI removed this from the intro: Feminization is the female counterpart to feminization, although they are not strictly opposite processes - for example, in some endocrine disorders, both virilizing and feminizing changes may occur simultaneously. It made the intro much less clear and is not part of the core definition. But it still needs to be worded more clearly before be replaced farther down in the article. It reminds me of the famous "this is not a pipe" sign accompanying a picture of a pipe, as its juxtaposition belies the second clause. alteripse 21:54, 12 June 2007 (UTC)
- Yeah, my bad, last edit before bed and I wrote "feminization" twice when I meant to write "Feminization is the female counterpart of virilization..." There's an important concept here, but it isn't well served by my poorly phrased sentence (even after fixing it) so I'll leave it alone until I can address the point more completely. -RustavoTalk/Contribs 01:42, 13 June 2007 (UTC)
Defeminization and masculization
editThe article was uncited so has been redirected here. It used to say
This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages)
|
Defeminization and masculinization are the processes that a fetus goes through to become a male. [citation needed]
It has often been said by biologists that in sexual differentiation in mammals, the female is the "default" developmental pathway, in the sense that elimination of any of several gene actions necessary for formation of male genitalia leads to the development of external female genitalia (though development of functional ovaries requires effective action of several less understood sex-specific genes). [citation needed] Two processes: defeminization, and masculinization, are involved in producing male typical morphology and behavior.
Defeminization involves the suppression of the development of female typical morphology (development of the Müllerian ducts into the fallopian tubes, uterus and vagina) and behavioural predispositions. Masculinization involves the production of male typical morphology (development of the Wolffian ducts into male reproductive structures) and behavioural predispositions. Both defeminization and masculinization are required for a mammalian zygote to become a fully reproductively functional male.
A brief version of the female default paradigm can be stated as follows:
- A set of specific genetic instructions must be present and a series of differentiating events mediated by hormones must occur in order for a mammalian zygote to become a fully reproductively functional male.
- The Y chromosome, SRY, SOX9, and SF1 genes must be present and functional.
- Functional Leydig cells must form in the gonads.
- The Leydig cells must be able to produce testosterone.
- The target cells must have the hormone receptors to respond to the testosterone. The target cells of the external genitalia must have functional 5-alpha-reductase enzyme to convert some of the testosterone to more active dihydrotestosterone.
- There is some evidence that the brain must be exposed and respond to androgens either prenatally or early in life to produce characteristic mating behavior. This is well demonstrated in many animal species but remains mostly speculative with respect to humans.
- To a large extent, each step builds on the previous. If anything goes wrong at any of the first four steps, the subsequent pathway of development results in female anatomy and behavior.
- No ovarian organizing gene homologous to SRY has been discovered. Both sexes are exposed to maternal estrogen prenatally. No hormones have yet been discovered that are necessary early in life to produce female sexual development. Estrogen seems not to be necessary until puberty for purposes of differentiation.
- The full development of male characteristics also includes personal experience throughout life[citation needed], determining gender identity, gender roles and sexual orientation. However, there is much debate on the balance between nature and nurture in the determination.
Update
editAfter doing a semi-deep dive on this topic (admittedly, as a non-biologist), the information in the above text is extremely outdated, and developmental biologists have switched to a much more complex and nuanced view of sexual differentiation - specifically that there are a lot of different genes and processes that actively stimulate male and female development, and sometimes these even overlap. Two good sources are [1] and [2]. I've added an overview of the above text to the article along with modern context of how the theory came to be abandoned. --Tserton (talk) 09:19, 6 July 2023 (UTC)
History
editThis paradigm dates back to the 1950s. Even stronger versions were commonly stated in the 1960s and 1970s. One version, perhaps most associated with John Money, (who termed it the Adam principle), held that additional steps in the cascade to male identity were the recognition by parents and doctor that the external genitalia were male, which resulted in a male sex assignment, which in turn resulted in a male sex of rearing by parents and society, which in turn (coupled with the reinforcing appearance of male genitalia) resulted in a male gender identity. At least by implication, female gender identity simply required a female sex of rearing and lack of an obvious penis.