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X Chromosome

Why can't humans survive without an X Chromosome? Just wondering. Because people can survive without a Y Chromosome but they can't survive without an X Chromosome.

Thanks! xx

Spoiler

(edited 6 years ago)
Bumpity Bump
Reply 2
Going to watch this thread because I'm also interested.

(nice pun btw)
Original post by TheEyeOfBaradDur
Why can't humans survive without an X Chromosome? Just wondering. Because people can survive without a Y Chromosome but they can't survive without an X Chromosome.

Thanks! xx

Spoiler




i have no idea if this is a reason, but X chromosomes are larger in size than the Y chromosome so it has more genes on it and thus more alleles?
Reply 4
XY= male
XX= female
X = Turner's Syndrome
Y = nothing
(edited 6 years ago)
X is the default blueprint for human development. All fetus start of as female as standard. Presence of the Y chromosome, causes adaption to male sex fetus. That's why the Y chromosome is so much smaller than the X, it's the changes required to morph the standard female into a male. That's why men have nipples, they started off as female. The male penis in a huge and modified clitoris etc.
Original post by kolajeex

X = nothing


Turner's Syndrome
Original post by hydroxide
i have no idea if this is a reason, but X chromosomes are larger in size than the Y chromosome so it has more genes on it and thus more alleles?


Ok that makes sense, thanks!
Reply 8
Original post by TheEyeOfBaradDur
Turner's Syndrome


corrected
Original post by 303Pharma
X is the default blueprint for human development. All fetus start of as female as standard. Presence of the Y chromosome, causes adaption to male sex fetus. That's why the Y chromosome is so much smaller than the X, it's the changes required to morph the standard female into a male. That's why men have nipples, they started off as female. The male penis in a huge and modified clitoris etc.


In Turner's Syndrome, part or the whole of 1 X Chromosome is missing. How come there isn't another disease where that happens in boys, because Turner's Syndrome only happens in girls?
Original post by TheEyeOfBaradDur
Ok that makes sense, thanks!


Exactly as what @hydroxide said.

What is more interesting is that research have found that the Y chromosome is actually "disappearing" which leads to scientists thinking that the Y chromosome may not actually be necessary for our existence.

Either that or we're fu*ked but you know
Original post by Lord Nutter
Exactly as what @hydroxide said.

What is more interesting is that research have found that the Y chromosome is actually "disappearing" which leads to scientists thinking that the Y chromosome may not actually be necessary for our existence.

Either that or we're fu*ked but you know


So there's only going to be one gender some day? Jesus!
Original post by Lord Nutter
Exactly as what @hydroxide said.

What is more interesting is that research have found that the Y chromosome is actually "disappearing" which leads to scientists thinking that the Y chromosome may not actually be necessary for our existence.

Either that or we're fu*ked but you know


more sex-linked diseases?
Original post by TheEyeOfBaradDur
In Turner's Syndrome, part or the whole of 1 X Chromosome is missing. How come there isn't another disease where that happens in boys, because Turner's Syndrome only happens in girls?


Female = XX

So if one X chromosome was damaged, or missing, there is at least one fully functioning X chromosome to act as a development 'blueprint'.

Male = XY

If the X chromosome was missing or damaged, the fetus wouldn't develop, therefore no male baby with Turner's

If the Y chromosome was missing, the default X blueprint wouldn't be 'updated' with the extra Y chromosome genetic code, therefore the fetus wouldn't change into a male, therefore it would be the same as for above, a female with only one X chromosome.
Original post by johnny.snow
more sex-linked diseases?


Quite possibly but lets just sit back and let natural selection do its business :cool:
Original post by Lord Nutter
Quite possibly but lets just sit back and let natural selection do its business :cool:


i mean, it would be against natural selection surely?
Original post by TheEyeOfBaradDur
In Turner's Syndrome, part or the whole of 1 X Chromosome is missing. How come there isn't another disease where that happens in boys, because Turner's Syndrome only happens in girls?



Just to expand a little on the other reply:

In a healthy, genetically typical female, one X chromosome is de-activated through a process called X-inactivation, which effectively removes gene duplicates. This is why females with Turner syndrome can survive as the other X chromosome they would have had would have been turned off anyway.

Your question is essentially "if you can have individuals with the karyotype X (as opposed to XX or XY) then why can't you have individuals with the karyotype Y?". This is simply because the Y chromosome is tiny and only really carries the information that causes a male foetus to develop the male phenotype (i.e. testes, penis and prostate). It doesn't contain enough genes to support life, so, while an embryo that has the karyotype Y could be conceived (if a Y sperm met an empty egg that was produced through a meiotic error), this embryo would be miscarried early on in the pregnancy (possibly before the woman even found out she was pregnant).

There are, however, other chromosomal diseases that affect men such as Kleinfelter's syndrome (where the karyotpe is XXY).
Original post by 303Pharma
X is the default blueprint for human development. All fetus start of as female as standard. Presence of the Y chromosome, causes adaption to male sex fetus. That's why the Y chromosome is so much smaller than the X, it's the changes required to morph the standard female into a male. That's why men have nipples, they started off as female. The male penis in a huge and modified clitoris etc.

That is actually quite sensible, to further add on this, on the y chromosome,it is the SRY gene in which the testis-determining factor promotes growth of sertoli cells which in turn secrete anti mullerian hormone and suppress the female character.

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