Let me preface this by stating that I'm a third-year Bio major currently taking graduate level courses in human genetics. I took a class this afternoon on epigenetics, and a couple of the things I learned brought X-23 to mind. I confirmed my suspicions with a bit of independent research on PubMed.
  
You cannot, biologically, make female clones of male humans.

 To cut a long paper short, X-23 has something called uniparental disomy for her maternal X chromosome (she has two copies of one of Wolverine's mother's X chromosomes, instead of a paternal and a maternal copy). For those of you who know anything about genetics, this is a very bad thing. The two copies you have of each chromosome are far from redundant. If they were, we'd have evolved monosomy long ago. In fact, you express a slightly different set of genes on each of them depending on whether you inherited it from your mother or your father. Your cells know which is which based on epigenetic modifications (addition of methyl or acetyl groups to the proteins around which your DNA is wrapped). See the problem? X-23 has two maternal X chromosomes.

 Now, a funny thing about girls is that having two X chromosomes in the first place is a little iffy. We guys get along just fine with only the one. So what happens is that one of a woman's two X chromosomes is inactivated in every cell in her body, at random. If you could scan a female's X chromosomes on Cerebra, she'd come up looking like a messy jigsaw puzzle in two colours. The silencing isn't complete, but it takes care of almost all the genes on the chromosome. This happens so that girls don't end up with twice the level of protein synthesis that guys do - which would be very bad thing indeed. By now you should have figured out where I'm going with this.

Geneticists have found from case studies that neither X chromosome gets inactivated in girls with maternal X isodisomy. The cells can't tell them apart, and so both hang around transcribing gene products. And to add to the problem, the fact that both X chromosomes are genetically and epigenetically identical means that the poor girl also manifests the problems associated with having only a single X chromosome (this is called Turner syndrome, and isn't so bad in comparison; you end up with a weird-looking body, infertility, and some cognitive deficits, none of which would merit a second glance among the X-men). But having two of the same X chromosome is far worse.

To quote symptoms from the only confirmed case of functional maternal X isodisomy in the literature (the rest die as embryos, thankfully):

• Extremely short stature (in the second percentile).
• A tiny head and low hairline.
• A short neck with "webbing"
• A deformed spine.
• Swelling and deformity of the hands and feet.
• Inability to straighten fingers, elbows and knees.
• Inverted nipples.
• Lack of sexual development.
• Severe breathing problems.
• Inability to walk.
• Inability to speak.
• Profound mental retardation.
• Brain abnormalities causing seizures.
• Extreme ugliness (all right, this is a paraphrase).
• Light stripes on her skin.
• Death at age 11 from cardiorespiratory and liver failure.

Dude....it's a comic book.

Well, she's going to have an arc with Mrs. Sinister, so perhaps they'll fix that.

It's comics. There has to be a certain suspension of belief.

" Dude....it's a comic book. "

In a world filled with mutants, aliens, god, and various other fantastic things the thing you have an issue with is a female clone of a male?

 
 
Galactus's body mass cannot begin to support the massive weight of his mighty purple short-shorts.
 

SCANDAL I SAY!

LMAO Well observed. had a good laugh from this envisioning how X-23 should really look like.
 
Isn't hse a clone as by definition of identical? I think her second X-chromosome came from Dr. Kinney who carried her out?

Yea that is bull crap they shouldn't have done that it's ridiculous just like her "father" having claws and able to regenerate limbs...........SHUT UP ITS COMICS

" Dude....it's a comic book. "

Several things: it is a comic book, as some people have said here. Also Dr. Kinney used the X chromosome as a base and did a lot of repair work. What if she fixed the issues? Not feasible in real life but in the comic book world...or, also as suggested in this thread, maybe one of the X chromosomes was from herself? X-23 is not a strict clone. She is more 'based' off Wolverine's DNA as closely as possible, designer DNA. Dr. Kinney repaired a lot of genes that had been destroyed, made up coding where it was missing. I assume, with all the possible opportunities, that the problem was solved through one of these avenues.

Is this guy trying to look for actual logic in comics? O_o 
 
Dude we know! Is not like we think a person can actually shoot lasers out of their eyes -__-  
 
The only possible "superpower" a real human being has is maybe flatulence which with the aid of a lighter it becomes a flame 
 
So, yeah, we have a flamethrower on our butts but is not a real super power, is not very potent and is incredibly embarrassing -__- 
 
That's as close to super powers as we'll get

" Is this guy trying to look for actual logic in comics? O_o   Dude we know! Is not like we think a person can actually shoot lasers out of their eyes -__-    The only possible "superpower" a real human being has is maybe flatulence which with the aid of a lighter it becomes a flame   So, yeah, we have a flamethrower on our butts but is not a real super power, is not very potent and is incredibly embarrassing -__-   That's as close to super powers as we'll get "

" @Band Lone said:

" Is this guy trying to look for actual logic in comics? O_o   Dude we know! Is not like we think a person can actually shoot lasers out of their eyes -__-    The only possible "superpower" a real human being has is maybe flatulence which with the aid of a lighter it becomes a flame   So, yeah, we have a flamethrower on our butts but is not a real super power, is not very potent and is incredibly embarrassing -__-   That's as close to super powers as we'll get "

Not true.  The same gene that allows jelly fish to regenerate and regrow limbs and what not is also present in the human genome.  It's just inactive, it's just a matter of someone or something activating what is already there.    So there ya go, humans have a healing factor....it's just that no one has figured out how to use it. "

You have difficulty to believe a change gender from a clone baby. It’s not that hard. But to spare DNA talk the female part came from her mother. X-23 is a test tube baby to be more exact.  Some DNA may alter from the other parent.    

This is funny!  No-one would ever know that Laura was really a man in disguise if you hadn't WikiLeaked the scientific proof!  ;)

" It is a good thing she has a healing factor, the character you descibed wouldn't have been the nice to look at. "

I'd just like to point out that a lot of the people saying "Dude it's a comic book" and arguing that you should suspend disbelief for comic  books, are probably the same people who applaud "realism" in comic books, and drone on and on about how comic characters are too perfect, and like characters walking around in civvies more often.
 
All I'm saying is, as soon as you try to go for "realism" in comic books, you have to address intelligent, factual arguments such as what this guy has presented.

"I'd just like to point out that a lot of the people saying "Dude it's a comic book" and arguing that you should suspend disbelief for comic  books, are probably the same people who applaud "realism" in comic books, and drone on and on about how comic characters are too perfect, and like characters walking around in civvies more often.  All I'm saying is, as soon as you try to go for "realism" in comic books, you have to address intelligent, factual arguments such as what this guy has presented. "

The way I read it, I thought  Dr. Sarah Kinney used only Wolverine's X chromosome and replaced the damaged Y one with one of her own, thereby making X-23 basically Wolverine's daughter by artificial insemination.

 @PumpkinBomb said:

" @jordama said:

" It is a good thing she has a healing factor, the character you descibed wouldn't have been the nice to look at. "

This would require her entering puberty during the first trimester. "

" This is funny!  No-one would ever know that Laura was really a man in disguise if you hadn't WikiLeaked the scientific proof!  ;) "

" The way I read it, I thought  Dr. Sarah Kinney used only Wolverine's X chromosome and replaced the damaged Y one with one of her own, thereby making X-23 basically Wolverine's daughter by artificial insemination.
"

you do relise there are characters in comic books that have fathered themselves? and other characters who alter reality witht there punches right?  

" @jordama said:

" It is a good thing she has a healing factor, the character you descibed wouldn't have been the nice to look at. "

This would require her entering puberty during the first trimester. "

she exists in a world where radioactive bugs give you super powers and occasionally a giant guy in purple armor shows up to eat the planet X23's origin isn't even a blip on the Marvel weird sh*t-o-meter

"
  @LucifersLawyer said:

" The way I read it, I thought  Dr. Sarah Kinney used only Wolverine's X chromosome and replaced the damaged Y one with one of her own, thereby making X-23 basically Wolverine's daughter by artificial insemination.
"

If Sarah Kinney has a Y chromosome then their family has more problems than X-23 being a clone "

" @hydrabob said:

"
  @LucifersLawyer said:

" The way I read it, I thought  Dr. Sarah Kinney used only Wolverine's X chromosome and replaced the damaged Y one with one of her own, thereby making X-23 basically Wolverine's daughter by artificial insemination.
"

If Sarah Kinney has a Y chromosome then their family has more problems than X-23 being a clone "

oh I laughed so hard I woke up butters 

on the matter of this thread... Does it really matter? I personally don't care on whether or not her "scientific origin" is accurate. she is one of the few marvel female characters that has her own solo series! "

Well we all know that everything in comic books is not very accurate or possible in the real world let's just keep on believing that it is okay :)

Well constant healing factor is all i have say, and that the scientist probably overide the mother x chromosome like they did with terry, u do know they can do that right

I think this is actually interesting, but, yeah, this is far from the most ridiculous thing in comics.

You should write a book about this stuff just like this book 

Science of the X-Men by Linc Yaco

I apologize; I don't mean to be the wise-ass who sidetracks what is a pretty interesting discussion, but since reading the forum header I can't get the image of a stalk of celery with adamantium claws out of my head.

I won't say "it's a comic book" because many other times comics tend to go for realistic matters, no? But in the case of X-23, maybe they were less realistic for the sake of getting a female clone. They probably knew it wasn't scientifically possible to get a female clone from a male as you pointed and out but wanted ignore the odds and facts for the character. Who knows, they probably debated over rather or not they wanted a male or female. *shrug* Nice observation though - never knew a clone could be the opposite sex of the original. 

" I'm surprised you dident pick on Hulk/Bruce banner for being unrealistic. "

" Dont forget Flash and Magneto! "

fortunately, the writer doesn't know JACK about human genetics and therefore X-23 is a perfectly functional (and quite hot) woman. tada.

"Dude....it's a comic book. "

one thing i would like to point out is that she is the 23rd attempt at a clone, i'm sure the geneticists did some sort of splicing in order to make the silencing of one of the chromosomes work

" This is funny!  No-one would ever know that Laura was really a man in disguise if you hadn't WikiLeaked the scientific proof!  ;) "

You can also not have a giant entity eat up a world, or have people running around with a coat of metal around their bones....thats why there comics :)