Masumi Sera's condition

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Swagnarok
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Masumi Sera's condition

Postby Swagnarok » July 16th, 2016, 1:57 pm

I'm probably looking too much into an insignificant detail, but here's my theory on Masumi Sera. First, some background information on genetics:

Asexual organisms (mostly single-celled organisms) reproduce through a method called Mitosis, in which the chromosomes of a cell are doubled before the cell splits in two.
Organisms that produce sexually, however, use a method called Meiosis. In human beings, the typical cell has 23 pairs of chromosomes, or 46 in total. During Meiosis, a cell simply splits into smaller components known as gametes. A gamete has 23 chromosomes in total, with no chromosome pairs. Whenever a male gamete and a female gamete combine, they form a zygote. The 23 chromosomes from each parent combine so that the zygote has 46 chromosomes, or 23 pairs, one pair from each parent. The first 22 pairs of chromosomes are called autosomes. However, the 23rd pair, which determines sex, is known as the allosome/sex chromosome pair.
A woman only has the XX allosomes, so during meiosis she can only donate an X pair. This is why all people, male or female, have an X allosome. A man has the XY allosomes, so he can donate either the X or Y chromosome, leaving a roughly 50/50 chance of the offspring being a boy or a girl. The default human gender, then, is female, but a single Y chromosome will result in male offspring, even if he has allosomal trisomy XXY or allosomal tetrasomy XXXY.
So, whenever an embryo is conceived, it will either automatically begin development of a female phenotype (if XX) or begin producing Androgens, which will prevent female development and begin male development (if XY).
However, it isn't always that simple. There are two conditions that can turn this whole equation upside down: Complete Androgen Insensitivity Syndrome (CAIS) and Swyer Syndrome. Under these two conditions, an embryo with an XY karyotype will not halt female development or begin male development. The end result is a phenotypically female person with the karyotype XY. These people will be born and raised female without knowing about their male DNA. However, they are not "perfect" women. Their bodies will not produce egg cells and they might not ever go through puberty (resulting in a totally flat-chested woman).

My theory is that Masumi Sera has either CAIS or Swyer Syndrome. If she has knowledge of this, she might not feel like a "real" girl, which would explain her boyish behaviour.
Again, I'm probably thinking too much into an insignificant detail, but what do you think?
Spoiler:
Cherry Blossoms raining down
Just like snow mingled with blood
The fallout from our terrible choices
From the heavens that have rejected us

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Spimer
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Re: Masumi Sera's condition

Postby Spimer » July 16th, 2016, 2:39 pm

@Swgnarok: welcome to the forums.

While you make some good points I've got the feeling Gosho's not going that far with Sera's character or the reason for her looks.

First she began as a character his editors wanted him to incorporate seeing the popularity of a girl detective in the Detective Koshien Case.

There are steorotypical girls that speak and behave and look like boys in Japanese manga from time to time.

In Sera's case, I believe that Gosho's just kidding around with that of the flat chest thing because it's the reason she gets mistaken for a guy: her behavior is that of a typical "tomboy", a girl who wants to be a boy.

Gosho hasn't touched much upon genetics: there was the whole blood type thing back when the Kir arc and we had a tale about different gender twins in Amuro's introduction case.

In any case, you've brought up some interesting points.
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Swagnarok
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Re: Masumi Sera's condition

Postby Swagnarok » July 16th, 2016, 2:50 pm

Spimer wrote:@Swgnarok: welcome to the forums.

While you make some good points I've got the feeling Gosho's not going that far with Sera's character or the reason for her looks.

First she began as a character his editors wanted him to incorporate seeing the popularity of a girl detective in the Detective Koshien Case.

There are steorotypical girls that speak and behave and look like boys in Japanese manga from time to time.

In Sera's case, I believe that Gosho's just kidding around with that of the flat chest thing because it's the reason she gets mistaken for a guy: her behavior is that of a typical "tomboy", a girl who wants to be a boy.

Gosho hasn't touched much upon genetics: there was the whole blood type thing back when the Kir arc and we had a tale about different gender twins in Amuro's introduction case.

In any case, you've brought up some interesting points.


I understand what you're saying, oh you glorious character from the Lugia movie.
Like you said, it's unlikely that Gosho Aoyama had this in mind. However, since details about the character are still vague, it's possible that he could add this detail in at some future date if he had some plot-related reason for doing so. Detective Conan is a show which doesn't like to keep mysteries unsolved indefinitely, so this might be touched upon eventually.
Spoiler:
Cherry Blossoms raining down
Just like snow mingled with blood
The fallout from our terrible choices
From the heavens that have rejected us

My fanfic account:
https://www.fanfiction.net/u/7291651/Swagnarok
k11chi
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Re: Masumi Sera's condition

Postby k11chi » July 16th, 2016, 3:55 pm

She's a tomboy...
Swagnarok
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Re: Masumi Sera's condition

Postby Swagnarok » July 16th, 2016, 4:41 pm

k11chi wrote:She's a tomboy...


Yes, that much has already been established.
Spoiler:
Cherry Blossoms raining down
Just like snow mingled with blood
The fallout from our terrible choices
From the heavens that have rejected us

My fanfic account:
https://www.fanfiction.net/u/7291651/Swagnarok
ATEM
Posts: 86

Re: Masumi Sera's condition

Postby ATEM » July 16th, 2016, 6:02 pm

I am not too much into genetics but I have studied it a bit...your theory is too complicated and I think gosho doesn't have a strong medical background as I know he has a brother who helps him when it comes to medicine so choosing such a complex not so much common diseases in a mystery manga series doesn't fit
he used genetics once where Amuro first appear as I am not too much into the subject I don't know if it's even medically possible as the division of zygote into two zygotes occurs after fusion not before but he also neglected other features of turner's syndrome it's not just about being short ..
he just wanted a medical condition to make the case possible and to match the DNA of the brother and sister .. so for sera to have a medical condition may be true if it serves gosho's plot for some reason ..but I don't see that gonna change anything ...

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