Chimera - PrologueMature

Medical issues spur a young girl to find out more about herself until reality begins to mix with the fantastic.

Running down the library steps and catching the late afternoon bus, Chimera plopped down into a seat.  She sat trying to take in all the information.  The librarian had been very helpful, assuming that Chimera was doing a school project.  Oh so wrong.  Chimera had in fact been checking out information about herself.  Half of the information she already knew had known since she was able to read.  The other, now that was the real wake up call.

Chimera reached into her backpack and grabbed out the wrinkled sheet again, rereading and trying to understand this wrench that the powers above decided to throw at her.  The Internet Wikipedia had given some real insight into her condition.  Again she read:

Typically seen in non-human zoology (but also discovered to a rare extent in human beings), a chimera is an animal that has two or more different populations of genetically distinct cells that originated in different zygotes; if the different cells emerged from the same zygote it is called a mosaicism.

Chimeras are formed from four parent cells (two fertilized eggs or early embryos fused together) or from three parent cells (a fertilized egg is fused with an unfertilized egg or a fertilized egg is fused with an extra sperm). Each population of cells keeps its own character and the resulting animal is a mixture of tissues.

This condition is either inherited, or it is acquired through the infusion of allogeneic hematopoietic cells during transplantation or transfusion. In nonidentical twins, chimerism occurs by means of blood-vessel anastomoses. The likelihood of a child being a chimera is increased if the child is created via in vitro fertilization. Chimeras can often breed, but the fertility and type of offspring depends on which cell line gave rise to the ovaries or testes; intersexuality and hermaphroditism may result if one set of cells is genetically female and another genetically male.

Tetragametic chimerism is a less common cause of congenital chimerism. It occurs through the fertilization of two ova by two sperm, followed by the fusion of the zygotes and the development of an organism with intermingled cell lines. This happens at a very early stage of development, such as that of the blastocyst. Such an organism is called a tetragametic chimera as it is formed from four gametes — two eggs and two sperm. Put another way, the chimera is formed from the merger of two nonidentical twins in a very early (zygote or blastocyst) phase. As such, they can be male, female, or hermaphroditic.

As the organism develops, the resulting chimera can come to possess organs that have different sets of chromosomes. For example, the chimera may have a liver composed of cells with one set of chromosomes and have a kidney composed of cells with a second set of chromosomes. This has occurred in humans, and at one time was thought to be extremely rare, though more recent evidence suggests that it is not as rare as previously believed. Most will go through life without realizing they are chimeras. The difference in phenotypes may be subtle (e.g., having a hitchhiker's thumb and a straight thumb, eyes of slightly different colors, differential hair growth on opposite sides of the body, etc) or completely undetectable. Another telltale of a person being a chimera is visible Blaschko's lines.

Affected persons are identified by the finding of two populations of red cells or, if the zygotes are of opposite sex, ambiguous genitalia and hermaphroditism alone or in combination; such persons sometimes also have patchy skin, hair, or eye pigmentation (heterochromia). If the blastocysts are of the same sex, it can only be detected through DNA testing, although this is a rare procedure. If the blastocysts are of opposite sex, genitals of both sexes are often formed, either ovary and testis, or combined ovotestes, in one rare form of intersexuality, a condition previously known as true hermaphroditism. As of 2003, there were about 30-40 documented human cases in the literature, according to New Scientist. Since hermaphroditic chimeras would be expected to be the one half of all chimeras, with purely male and purely female chimeras being one-quarter each, this would suggest that the condition is not particularly common.

Natural chimeras are almost never detected unless the offspring has abnormalities such as male/female or hermaphrodite characteristics or skin discolouring. The most noticeable are some male tortoiseshell cats or animals with ambiguous sex organs.

Chimerism can be detected in DNA testing. The Lydia Fairchild case, for example, was brought to court after DNA testing showed that her children could not be hers, since DNA did not match. The charge against her was dismissed when it became clear that Lydia was a chimera, with the matching DNA being found in her cervical tissue. Another case was that of Karen Keegan.

The tetragametic state has important implications for organ or stem cell transplantation. Chimeras typically have immunologic tolerance to both cell lines. Thus, for a tetragametic human, a wider array of relatives and other persons may be eligible to be an organ donor.  Chimerism also shows, under infrared light, distinctive marks on the back resembling that of arrow points pointing downwards from the shoulders down to the lower back.

In Greek mythology, the Chimera (Greek Χίμαιρα (Chímaira); Latin Chimaera) was a monstrous fire-breathing creature of Lycia in Asia Minor, composed of the parts of multiple animals: upon the body of a lioness with a tail that terminated in a snake's head, the head of a goat arose on her back at the center of her spine. The Chimera was one of the offspring of Typhon and Echidna and a sibling of such monsters as Cerberus and the Lernaean Hydra. The term chimera has also come to mean more generally, an impossible or foolish fantasy.

She read the wikipedia quote over and over again, certain that at any minute these words would be somehow different, but here they were hovering in her face.  Chimera.  Her own name gave it all away.  Oh how her mother must have loved her to do this to her, she thought sarcastically.

Chimera; was for lack of words, different.  She had always been.  Looks, attitude and even physical makeup.  Early years had been a repeat of surgeries to make her “look” normal.  Normal, what was that?  So, she wasn’t actually a she but rather a combination of both male and female or hermaphrodite.

The resulting surgeries made her into the female she was.  She was blessed with the knowledge that the cells she had within her were a combination of four donors.  Her mother, the ever-loving slut she was making a twin for Chimera, and her two fathers.  The doctors had said that she must have fused with her twin during gestation.

Once Chimera was born and her mother knew what was going on.  She soon had Chimera shipped out into the system and lost to the world.  Oh the government made sure that their little darling was taken care of but at what cost.  Chimera was what she was.  A monster; in a world that didn’t believe there were monsters anymore.

Flicking a tear away, she put the paperwork back into her bag and looked around.  The bus wasn’t that full and the people that were there ignored her.  She was safe for the moment.  Breathing a sigh, she scrunched down in her seat and tried to make herself as small as possible.  Soon enough she would be back at the half way house.

Chimera heard the side doors open and close.  She ignored them, and was almost asleep when a hand fell on her shoulder.  She went into high gear from a doze into a whirl.  Grabbing the wrist and with a jerk almost had the person over her shoulder before she stopped.  What made her stop was the smell.  She knew it, a mixture of wood smoke, grease and Old Spice.  That alone halted her in her movements.  The wood smoke was from the pit where the meat was smoked and the grease was from the meat as it sizzled on the spit.  The Old Spice was the cologne worn.  It was the best smell in the whole world to her.  Her Dad.  Her world.  Someone who had never let the fact that she was a monster unsettle him in the least.  She was home.

The End

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