Dear anonymous coward: I realize you are anguished by your post being ignored, but few will waste mod points on an anonymous post unless it's truly earthshattering. I didn't see your post, because unless I have mod points, I have the threshold set to "1". Setting it to "0" shows too many AC flamer posts.
http://science.slashdot.org/comments.pl?cid=6665 839&sid=74320 for the curious.
Also, you have to depend on your post being seen by someone who understands what you are saying. And here is your third obstacle:
It would also help if your story had some scientific accuracy to it, not tabloid-style hyperbole.
Re:And another genetic anomaly heard from
on
Chimera Twins Story
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· Score: 1
My error... that's females with a single X
no "X" = no chance of developing into a human
The various degrees of testicular feminization were much more common than any of the other causes of ambiguous genitalia (what most non-medical would call "hermaphrodite") in the cases we diagnosed. They were followed by the various XY number problems. I don't recall a true somatic hermaphrodite mosaic, and one of them would have caused a memorable stampede of interns to the lab to look at the slides, and been the subject of some in-house presentations.
It's partly genetic and partly hormone controlled - the wonder is that so many people are anatomically normal. In a tetragamete mammal, the merging happens at a very early stage (the multicell blob stage), so the cells are quite jumbled. As they organize and differentiate, it would be quite rare to have both XX and XY cells end up in the right areas, and have the XX cells be unaffected by the early testosterone release from the XY ones and continue to develop into ovaries and a uterus. (that said, one person from Canada was reportedly male enough to have traditional male/female sex, and female enough to become pregnant, although it resulted in a stillbirth... this kind of case is so rare it gets presented at medical conferences)
What if (and this is a big "if", just for the exercise) SCO's copyrights were infringed upon and it unwittingly distributed those infringments via the Linux kernel. Does that mean that their copyrights are automatically invalidated and GPL-ized? No, of course not.
There is a legal process to follow if you discover that your works have been infringed upon. It involves filing a complaint in the appropriate court, and the complaint HAS TO SPECIFY exactly what part of work "A" is infringed upon by work "B". That is something SCO has not yet done. And a judge will not accept "they have some of our stuff in their stuff, trust me" as proof. I've been thorugh one infringement case and it was very meticulous: we showed our copyright, we showed our material in toto, and with the parts that appeared nearly verbatim in their material highlighted... they countered by trying to claim that thye had accidentally produced the same maerial as ours... down to my Canadian spelling quirks and three examples I made up. They lost.
US copyright law also specifies that this complaint must be begun within three years of the discovery of the infringement. SCO has pissed away over a year of it, if Darl is to be believed.
If the GPL were shot down, the default is copyright law. The GPL grants right in addition to the right inherent in acquiring a copyrighted object... the right to modify and distribute, with certain restrictions such as making source code available.
If you fail to follow the terms, and distribute without allowing othres the right to do the same, you lose the GPL protection and are immediately in violation of copyright... and every individual who has a line of code in that distro can claim infringement.
"The complaint fails to state a claim upon which relief can be granted." Translation: your entire case is not even salable as toilet paper
Even better is what IBM admits to:
admits that Sequent was formerly an Oregon corporation which was subsequently merged into IBM Admits IBM does business in Utah and maintains offices there
admits that UNIX operating systems are used by corporations.
admits that AT&T Licensed cretain software to IBM and Sequent
admits that IBM develops, manufactures and markets a UNIX product
admits that IBM markets a UNIX product under the the trade name AIX
admits that Sequent marketed a UNIX product under the trade name DYNIX/ptx
states that IBM develops, manufactures and markets a UNIX product under the the trade name AIX
admits that IBM POWER chips are currently more powerful than the Intel chips described in the averments admits that Unix-ware ran on Intel-based processors
admits that IBM and the Santa Cruz Ooperation, Inc. started Project Monterey (they carefully point out that this entity is now Tarantella, and has nothing to do with the SCO who is suing them)
Admits that the Santa Cruz Operation, Inc. provided information concerning UnixWare and certain software
Admits that AT&T licensed certain operating system software code to IBM (refers to the license agreement)
Admits that IBM has increased its IBM Global Services Staff
"admits that IBM lawfully uses certain software products and source code"
admits that IBM is subject to the laws of the United States
Re:This Raises Some Interesting Questions..
on
Chimera Twins Story
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· Score: 1
"It sounds like that's something that is programmed during the embryonic stage, as opposed to being determined genetically."
Exactly. I don't have my immunology books handy, but before a certain stage of development the developing mammal is immunologically "naive" (mayb fish and birds too - we didn't discuss them). If researchers make a transplant of tissue from another animal during this stage, it's accepted just as if it came from the recipient, and after birth, the mammal will not attack other transplants from that donor. It's as if they take an "inventory" at a certain point, and anything not in the inventory will be attacked as foreign.
"This Fortune 500 company recognizes the importance of paying for SCO's intellectual property that is found in Linux and can now run Linux in their environment under a legitimate license from SCO. Anyone wanna bet it's Microsoft?
I'm a bit fuzzy on the GPL, but as SCO has claimed to have successfully charged an unspecified user an unspecified amount of money for the use of Linux, and done so under terms which (if they used the license they were talking about) do not give the user access to the source code, just "run time binaries", can the kernel developers formally inform SCO that the "SCO license" does not include the use of any modules that those developers have copyrighted because SCO just violated the GPL in a big way?
I suppose you could subpoena SCO for the name of the company with the license so you can tell that company that they have to use SCO UNIX because SCO's has no legal right to license Linux.
Re:And another genetic anomaly heard from
on
Chimera Twins Story
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· Score: 1
No... the typical XXX female is short, dumpy and with facial malformations and extra skin folds on the neck.
Many female porn stars have has minor plastic surgery to make their clitoris look longer. (the things surgeons will chat about over coffee!)
No, but your chances are really good, like many hundreds to one.
Male cats with the XXY (abnormal) chromosome count can be calico or tortoise shell if they got the right color genes from the parents. There was a BIG research study on them in the 1970s (AFAIK, at Duke) and the amount of the second color ranged from the usual 50/50 split to a few animals that only had a small blotch of the second color. What surprised the researchers was that there were a LOT of them, and they weren't all sterile wimps. The lower the amount the secondary color, the more likely they were to act like normal males... some had even sired kittens.
Re:This Raises Some Interesting Questions..
on
Chimera Twins Story
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· Score: 0, Offtopic
Why cats are better than men: 1. A cat always comes in SOBER after being out all night. 2. When a cat goes to the toilet he tries not to leave a trace. 3. You can put a bell around a cat's neck so you know exactly where he is. 4. If you stroke a cat he won't leap on you for sex. 5. You don't mind that much if a cat brings a bird home every night. 6. When a cat comes in at mid-night it doesn't wake you up by smashing into every item of furniture. 7. Cats never pretend they know how to fix the video. 8. Cats don't care what size your boobs are. 9. Cats still love you even when your perm goes wrong. 10. Cats love rubbing up to your legs however much cellulite you have. 11. Cats can be neutered if they stray. 12. If a cat jumps into your lap, a little light petting will satisfy him. 13. It's okay if a cat rubs up against your best friend. 14. If you ask enough times, a cat may actually listen to you. 15. You never have to spend time with your cat's mother. 16. Better chance of training a cat. 17. Cats are cute. 18. A cat is never late for dinner. 19. Cats love to see you come home from shopping with lots of bags! 20. You'll never get a call from your cat's ex-wife. 21. A cat would never leave you for a younger women. 22. Cats treat your mom with respect. 23. Cats don't worry about hair loss. 24. It feels nice to stroke a cats soft, fluffy fur. 25. A cat's friend is less likely to be annoying. 26. Cats can't show love without meaning it. 27. To buy a fancy dinner for a cat only costs 40p 28. Cats actually think with their heads. 29. Unlike a man, a cat can fend for itself. 30. It is legal in all states to neuter a cat. 31. Cats comfort you when you are sick. 32. When a cat sleeps all day it's natural, not annoying.
Why cats are better than women: You don't have to contend with mothers in law. Cats dont use your credit cards. Cats don't hog the bathroom for hours. Cats don't need a new dress every time they go out. Cats don't have PMS. (whoever wrote this clearly never had an unaltered female cat) Cats always look good first thing in the morning. Cats never question your decisions. Cats don't complain about how much you eat or the way you dress. A cat won't scream if it sees a mouse in the house. Cats don't ask "Am I getting fat?" and expect you to lie. Cats don't call the lawyers if you sleep with another cat. Cats dont object to kisses just because you haven't shaved. Cats don't expect expensive presents on their birthday. Cats never make you sleep in the spare bedroom.
(you male or female?) It is quite possible you are a "blood chimera"... the fetal cells that became what now makes your blood could easily have moved between the two of you. (if you are a blood chimera, it's quite likely he is too).
Get your twin to volunteer for studies done on fraternal and identical twins with you. Otherwise, it's not something anyone worries about.
"Wouldn't the body be compatible with boths sets of dna?"
Yes. Whatever cell antigens are around during fetal development are tolerated in adulthood. And you don't DNA type for transplants, you use cell surface antigens. It might or might not make them easier to find donors for.
These chimeras and mosaics have the two cell lines from th etow fertile eggs intermingled throughout their bodies - it's not a case of having a heart from one, a liver from the other. They merge WAY earlier than that.
No. It's a single-point mutation in the eye color gene in the cells that make up the eye... it can appear as just a radiating patch of the color in one eye all the way to being truly odd-eyed depending on when in the eye's development the mutation happened.
"then there may be something in there to allow for selectively suppressing an immunoresponse (sp?) that could be valuable."
No. It's the well-known fetal tolerance effect... she was thoroughly exposed to her brother's cells during gestation, and has some of her brothers cells even now. From the description, prehaps some of her mum's too.
More interesting to immunologists and transplant surgeons: why doesn't the mother's body detect the developing placenta/fetus and KILL it? They would kill transplants later. There are some problems (erythroblastosis foetalis) but most come through with no problems.
NO... The antigens you are exposed to in utero are "self" and would not cause a problem at all. The developing fetus "takes an inventory" late in the development process and everything that is there at that time is not attacked by the immune system. This would be months after the two fertilized eggs or early multi-cell blobs merged.
Nice thought, and bone marrow transplants are matched for blood and some tissue types.
You would have to be careful to not leave hair, semen or skin cells because they would have the "old" DNA in them.
The immune system will tolerate any antigens that it is exposed to at an early stage of fetal development. At a point that varies with each species, the immune system appears to take an inventory of "my cells and their surface antigens" and from then on it will attack anything not recognized as "self".
Re:Physical issues resulting from this?
on
Chimera Twins Story
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· Score: 2, Informative
Oh, that woman. She is a "blood chimera"... the red blood cells in her body have a population from her and one from her twin because of merged blood vessels in the placentas. This can sometimes give some misleading tests when ordinary ABO/rH testing is used. She was not a "tissue chimera", which would be an individual with mixed populations in the other tissues, such as ovaries, skin, heart, etc.
"is this a possible explaination for hermaphrodites? "
No. Most hermaphrodites have DNA for one person - not two distinct cell populations from two separately fertilized eggs.
Usually cases of "ambiguous gender" are the result of
"testicular feminization",... genetically they are XY males, but because of an inherited trait on the X chromosome from their mom, they develop physically as female... partially or to the extent that only their gynecologist could tell the difference.
The two I remember from doing lab tests in a fertility clinic were very "female" looking. And no, we didn't say "guess what, you are really a man" when the chromosome testing came back because they aren't. The default state for humans is female unless testesterone is produced by the fetus AND the fetus responds to it.
Cats show this deactivation clearly... the orange and black colors are on the X chromosome in them. The blotched black/orange (or cream/grey) coloration of a tortoiseshell or calico shows that the two X chromosomes were inactivated separately and randomly.
"Would it be possible to have two blood types? Surely not, but as I do not have any way to listen to the link I will never know until some kind soul gives us the gist of it."
IANAL, but IUTWIBB... I used to work in blood banks doing crossmatches. A small number of people have two different ABO blood types. They are not "AB", they have some red blood cells that are pure "A" and some that are pure "B" and that is violating Mendelian genetics. The same mechanism that creates this could easily create other "blood chimeras" with the other several hundred lesser-known blood types. And a third mechanism (sex chromosome abnormalities) can create a kind of blood chimera that has nothing to do with twins.
Apparently, most of these blood chimera individuals shared a blood supply with a non-identical twin before birth (the cells that make blood and populate your bone marrow float around the fetal blood supply while waiting for bones to develop to give them a place to settle, and the placentas and their blood vessels can merge without producing conjoined twins). In some cases, people are unaware that they had a twin because he or she died early in gestation and was spontaneously aborted (or disintegrated by the mother's defense mechanisms, or walled off in the mother or living twin). They show up in the National Enquirer when someone is operated on for a cyst and it has bits of the encysted twin in it.
As many as 8% of non-identical twins may have chimeric blood. Some people are microchimeric--they have a small amount of blood of a different type in their system that has persisted from a blood transfusion or passed across the placental barrier from their mother before birth.
"Blood chimerism" does NOT cause a problem for the person with the chimerism as far as receiving blood in a transfusion... they will tolerate any phenotype they possess if you transfuse it - they have had it since they were fetuses and it is "self" in the immunological sense of the word.
It can, however, be hell on blood banks trying to figure out what the heck is wrong with the blood during the initial typing and screening in a transfusion where the blood chimera is the donor. The potential recipient is not at risk because the tech says &^$^$#%@!!!, sets the donor unit back in the frig with a "do not use" note and sends it off to a research lab to find out what's going on. That's how you usually find blood chimeras and new blood types... anomalous results in what should be a routine crossmatch.
And another genetic anomaly heard from
on
Chimera Twins Story
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· Score: 5, Informative
It doesn't take "chimerism" to get this effect. The well-known variations in the number of sex chromosomes can also do it, and they can happen in the cell division process.
Normal male = Xy (any extra "X" are abnormal, but even a XXXXy is still male - all but one X gets deactivated - but usually has serious medical problems). Normal female = XX (extra "X"s do not create supermodels, it creates medical problems)
Take a look at any calico or tortoise shell cat. What you are seeing is the result of random deactivation of one of the X chromosome early in the development of the embryo, and the random appearance of the colors (black or orange) on that chromosome. Humans have few easily testable traits that are testible for chimerism: one blood group is all I can think of at the moment, that "lives" on the X chromosome.
For calico or tortie males (yes, they exist, and no they are not valuable) the division between the colors is a good indicator of how badly screwed up their sex chromosomes are. A male that is mostly orange with one small black patch probably acts like a tomcat and will show very few cells of the XXY pattern, and might even have that abnormality limited to that spot. One that is well-mottled with black and orange is probably not interested in breeding and will show mnay more abnormal XXY cells.
In order to test this for the possibility to screw up DNA identification, they could start by testing the known chimeras - cats.
Slashdot Mirror
http://science.slashdot.org/comments.pl?cid=6665 839&sid=74320 for the curious.
Also, you have to depend on your post being seen by someone who understands what you are saying. And here is your third obstacle:
It would also help if your story had some scientific accuracy to it, not tabloid-style hyperbole.
My error ... that's females with a single X
no "X" = no chance of developing into a human
It's partly genetic and partly hormone controlled - the wonder is that so many people are anatomically normal. In a tetragamete mammal, the merging happens at a very early stage (the multicell blob stage), so the cells are quite jumbled. As they organize and differentiate, it would be quite rare to have both XX and XY cells end up in the right areas, and have the XX cells be unaffected by the early testosterone release from the XY ones and continue to develop into ovaries and a uterus. (that said, one person from Canada was reportedly male enough to have traditional male/female sex, and female enough to become pregnant, although it resulted in a stillbirth ... this kind of case is so rare it gets presented at medical conferences)
http://www.urologyhealth.org/pediatric/index.cfm ?cat=01&topic=110
u man_sexual_differentiation.html
http://www.gfmer.ch/Books/Reproductive_health/H
There is a legal process to follow if you discover that your works have been infringed upon. It involves filing a complaint in the appropriate court, and the complaint HAS TO SPECIFY exactly what part of work "A" is infringed upon by work "B". That is something SCO has not yet done. And a judge will not accept "they have some of our stuff in their stuff, trust me" as proof. I've been thorugh one infringement case and it was very meticulous: we showed our copyright, we showed our material in toto, and with the parts that appeared nearly verbatim in their material highlighted ... they countered by trying to claim that thye had accidentally produced the same maerial as ours ... down to my Canadian spelling quirks and three examples I made up. They lost.
US copyright law also specifies that this complaint must be begun within three years of the discovery of the infringement. SCO has pissed away over a year of it, if Darl is to be believed.
If you fail to follow the terms, and distribute without allowing othres the right to do the same, you lose the GPL protection and are immediately in violation of copyright ... and every individual who has a line of code in that distro can claim infringement.
"The complaint fails to state a claim upon which relief can be granted." Translation: your entire case is not even salable as toilet paper
Even better is what IBM admits to:
admits that Sequent was formerly an Oregon corporation which was subsequently merged into IBM
Admits IBM does business in Utah and maintains offices there
admits that UNIX operating systems are used by corporations.
admits that AT&T Licensed cretain software to IBM and Sequent
admits that IBM develops, manufactures and markets a UNIX product
admits that IBM markets a UNIX product under the the trade name AIX
admits that Sequent marketed a UNIX product under the trade name DYNIX/ptx
states that IBM develops, manufactures and markets a UNIX product under the the trade name AIX
admits that IBM POWER chips are currently more powerful than the Intel chips described in the averments
admits that Unix-ware ran on Intel-based processors
admits that IBM and the Santa Cruz Ooperation, Inc. started Project Monterey (they carefully point out that this entity is now Tarantella, and has nothing to do with the SCO who is suing them)
Admits that the Santa Cruz Operation, Inc. provided information concerning UnixWare and certain software
Admits that AT&T licensed certain operating system software code to IBM (refers to the license agreement)
Admits that IBM has increased its IBM Global Services Staff
"admits that IBM lawfully uses certain software products and source code"
admits that IBM is subject to the laws of the United States
bad cut and paste?
Exactly. I don't have my immunology books handy, but before a certain stage of development the developing mammal is immunologically "naive" (mayb fish and birds too - we didn't discuss them). If researchers make a transplant of tissue from another animal during this stage, it's accepted just as if it came from the recipient, and after birth, the mammal will not attack other transplants from that donor. It's as if they take an "inventory" at a certain point, and anything not in the inventory will be attacked as foreign.
I'm a bit fuzzy on the GPL, but as SCO has claimed to have successfully charged an unspecified user an unspecified amount of money for the use of Linux, and done so under terms which (if they used the license they were talking about) do not give the user access to the source code, just "run time binaries", can the kernel developers formally inform SCO that the "SCO license" does not include the use of any modules that those developers have copyrighted because SCO just violated the GPL in a big way?
I suppose you could subpoena SCO for the name of the company with the license so you can tell that company that they have to use SCO UNIX because SCO's has no legal right to license Linux.
Many female porn stars have has minor plastic surgery to make their clitoris look longer. (the things surgeons will chat about over coffee!)
Male cats with the XXY (abnormal) chromosome count can be calico or tortoise shell if they got the right color genes from the parents. There was a BIG research study on them in the 1970s (AFAIK, at Duke) and the amount of the second color ranged from the usual 50/50 split to a few animals that only had a small blotch of the second color. What surprised the researchers was that there were a LOT of them, and they weren't all sterile wimps. The lower the amount the secondary color, the more likely they were to act like normal males ... some had even sired kittens.
Why cats are better than men:
1. A cat always comes in SOBER after being out all night.
2. When a cat goes to the toilet he tries not to leave a trace.
3. You can put a bell around a cat's neck so you know exactly where he is.
4. If you stroke a cat he won't leap on you for sex.
5. You don't mind that much if a cat brings a bird home every night.
6. When a cat comes in at mid-night it doesn't wake you up by smashing into every item of furniture.
7. Cats never pretend they know how to fix the video.
8. Cats don't care what size your boobs are.
9. Cats still love you even when your perm goes wrong.
10. Cats love rubbing up to your legs however much cellulite you have.
11. Cats can be neutered if they stray.
12. If a cat jumps into your lap, a little light petting will satisfy him.
13. It's okay if a cat rubs up against your best friend.
14. If you ask enough times, a cat may actually listen to you.
15. You never have to spend time with your cat's mother.
16. Better chance of training a cat.
17. Cats are cute.
18. A cat is never late for dinner.
19. Cats love to see you come home from shopping with lots of bags!
20. You'll never get a call from your cat's ex-wife.
21. A cat would never leave you for a younger women.
22. Cats treat your mom with respect.
23. Cats don't worry about hair loss.
24. It feels nice to stroke a cats soft, fluffy fur.
25. A cat's friend is less likely to be annoying.
26. Cats can't show love without meaning it.
27. To buy a fancy dinner for a cat only costs 40p
28. Cats actually think with their heads.
29. Unlike a man, a cat can fend for itself.
30. It is legal in all states to neuter a cat.
31. Cats comfort you when you are sick.
32. When a cat sleeps all day it's natural, not annoying.
Why cats are better than women:
You don't have to contend with mothers in law.
Cats dont use your credit cards.
Cats don't hog the bathroom for hours.
Cats don't need a new dress every time they go out.
Cats don't have PMS. (whoever wrote this clearly never had an unaltered female cat)
Cats always look good first thing in the morning.
Cats never question your decisions.
Cats don't complain about how much you eat or the way you dress.
A cat won't scream if it sees a mouse in the house.
Cats don't ask "Am I getting fat?" and expect you to lie.
Cats don't call the lawyers if you sleep with another cat.
Cats dont object to kisses just because you haven't shaved.
Cats don't expect expensive presents on their birthday.
Cats never make you sleep in the spare bedroom.
Get your twin to volunteer for studies done on fraternal and identical twins with you. Otherwise, it's not something anyone worries about.
Yes. Whatever cell antigens are around during fetal development are tolerated in adulthood. And you don't DNA type for transplants, you use cell surface antigens. It might or might not make them easier to find donors for.
These chimeras and mosaics have the two cell lines from th etow fertile eggs intermingled throughout their bodies - it's not a case of having a heart from one, a liver from the other. They merge WAY earlier than that.
No. It's a single-point mutation in the eye color gene in the cells that make up the eye ... it can appear as just a radiating patch of the color in one eye all the way to being truly odd-eyed depending on when in the eye's development the mutation happened.
No. It's the well-known fetal tolerance effect ... she was thoroughly exposed to her brother's cells during gestation, and has some of her brothers cells even now. From the description, prehaps some of her mum's too.
More interesting to immunologists and transplant surgeons: why doesn't the mother's body detect the developing placenta/fetus and KILL it? They would kill transplants later. There are some problems (erythroblastosis foetalis) but most come through with no problems.
NO ... The antigens you are exposed to in utero are "self" and would not cause a problem at all. The developing fetus "takes an inventory" late in the development process and everything that is there at that time is not attacked by the immune system. This would be months after the two fertilized eggs or early multi-cell blobs merged.
Nice thought, and bone marrow transplants are matched for blood and some tissue types. You would have to be careful to not leave hair, semen or skin cells because they would have the "old" DNA in them.
The immune system will tolerate any antigens that it is exposed to at an early stage of fetal development. At a point that varies with each species, the immune system appears to take an inventory of "my cells and their surface antigens" and from then on it will attack anything not recognized as "self".
Oh, that woman. She is a "blood chimera" ... the red blood cells in her body have a population from her and one from her twin because of merged blood vessels in the placentas. This can sometimes give some misleading tests when ordinary ABO/rH testing is used. She was not a "tissue chimera", which would be an individual with mixed populations in the other tissues, such as ovaries, skin, heart, etc.
No. Most hermaphrodites have DNA for one person - not two distinct cell populations from two separately fertilized eggs.
Usually cases of "ambiguous gender" are the result of "testicular feminization", ... genetically they are XY males, but because of an inherited trait on the X chromosome from their mom, they develop physically as female ... partially or to the extent that only their gynecologist could tell the difference.
The two I remember from doing lab tests in a fertility clinic were very "female" looking. And no, we didn't say "guess what, you are really a man" when the chromosome testing came back because they aren't. The default state for humans is female unless testesterone is produced by the fetus AND the fetus responds to it.
Cats show this deactivation clearly ... the orange and black colors are on the X chromosome in them. The blotched black/orange (or cream/grey) coloration of a tortoiseshell or calico shows that the two X chromosomes were inactivated separately and randomly.
IANAL, but IUTWIBB ... I used to work in blood banks doing crossmatches. A small number of people have two different ABO blood types. They are not "AB", they have some red blood cells that are pure "A" and some that are pure "B" and that is violating Mendelian genetics. The same mechanism that creates this could easily create other "blood chimeras" with the other several hundred lesser-known blood types. And a third mechanism (sex chromosome abnormalities) can create a kind of blood chimera that has nothing to do with twins.
Apparently, most of these blood chimera individuals shared a blood supply with a non-identical twin before birth (the cells that make blood and populate your bone marrow float around the fetal blood supply while waiting for bones to develop to give them a place to settle, and the placentas and their blood vessels can merge without producing conjoined twins). In some cases, people are unaware that they had a twin because he or she died early in gestation and was spontaneously aborted (or disintegrated by the mother's defense mechanisms, or walled off in the mother or living twin). They show up in the National Enquirer when someone is operated on for a cyst and it has bits of the encysted twin in it.
As many as 8% of non-identical twins may have chimeric blood. Some people are microchimeric--they have a small amount of blood of a different type in their system that has persisted from a blood transfusion or passed across the placental barrier from their mother before birth.
"Blood chimerism" does NOT cause a problem for the person with the chimerism as far as receiving blood in a transfusion ... they will tolerate any phenotype they possess if you transfuse it - they have had it since they were fetuses and it is "self" in the immunological sense of the word.
It can, however, be hell on blood banks trying to figure out what the heck is wrong with the blood during the initial typing and screening in a transfusion where the blood chimera is the donor. The potential recipient is not at risk because the tech says &^$^$#%@!!!, sets the donor unit back in the frig with a "do not use" note and sends it off to a research lab to find out what's going on. That's how you usually find blood chimeras and new blood types ... anomalous results in what should be a routine crossmatch.
Normal male = Xy (any extra "X" are abnormal, but even a XXXXy is still male - all but one X gets deactivated - but usually has serious medical problems). Normal female = XX (extra "X"s do not create supermodels, it creates medical problems)
Take a look at any calico or tortoise shell cat. What you are seeing is the result of random deactivation of one of the X chromosome early in the development of the embryo, and the random appearance of the colors (black or orange) on that chromosome. Humans have few easily testable traits that are testible for chimerism: one blood group is all I can think of at the moment, that "lives" on the X chromosome.
For calico or tortie males (yes, they exist, and no they are not valuable) the division between the colors is a good indicator of how badly screwed up their sex chromosomes are. A male that is mostly orange with one small black patch probably acts like a tomcat and will show very few cells of the XXY pattern, and might even have that abnormality limited to that spot. One that is well-mottled with black and orange is probably not interested in breeding and will show mnay more abnormal XXY cells.
In order to test this for the possibility to screw up DNA identification, they could start by testing the known chimeras - cats.
Or should that be horrour?