Human parthenogenesis?

Discussion in 'Biology & Genetics' started by Buckaroo Banzai, May 15, 2004.

  1. Buckaroo Banzai Mentat Registered Senior Member

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    I've read in some places, briefly statements that is possible to a woman get pregnant of hersef, by her egg being fertilized by one of her polar corpuscles. This is true? Is it only possible, or have already happened? (can't be Jesus, from this sort of thing wouldn't result any male :p )
     
  2. eddymrsci Beware of the dark side Registered Senior Member

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    wow, that sounds pretty interesting. I once did some research on parthenogenesis for a science project, and I thought the process occurs consistently only in relatively simpler organisms such as aphids and possibly even ants.
    (have you seen Jurassic Park, those female dinosaurs underwent parthenogenesis in order to reproduce :p haha but that's only fiction)
    Well, "Life will find a way..." (From Jurassic Park):)
     
  3. Buckaroo Banzai Mentat Registered Senior Member

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    There's also at least a species of rock lizards, Lacerta unisexualis... I've found a paper about that somewhere in the internet once.
     
  4. eddymrsci Beware of the dark side Registered Senior Member

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    oh that's neat, let me be honest with you, for that science project, I was trying to test if parthenogenesis occurs in fruit flies (Drosophila Melanogaster) under certain conditions, and the results were negative. :(
     
  5. Enigma'07 Who turned out the lights?!?! Registered Senior Member

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    I've heard about those lizards before in a biology class. They said that the offspring is essantionialy a clone of it's mother.
     
  6. ElectricFetus I'm just going for a walk... Valued Senior Member

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    Ya hypothetically its possible, but I have never heard of a proven case of it happening in humans let alone mammals (well except for that one time were they made a mouse give birth to its own clone). By the way a women could only have a girl by parthenogenesis, it would not be a clone genetically because the genes have all be rearranged but it would likely look like a clone.
    There are many biologist trying to develop theories that explain how it s impossible, kind of like how physicist making theories on how time travel should be impossible.
     
  7. Buckaroo Banzai Mentat Registered Senior Member

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    Altough that I certainly agree that it is very improbable, I'd not say confidently that's impossible... not after hearing about a thing that suposed happened with a woman in Italy, is said that she gave birth to his baby, and then they verified that she was still pregnant of twins... I do not know how it managed to occur... if really occurred. :bugeye:
     
  8. weebee Registered Senior Member

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  9. Enigma'07 Who turned out the lights?!?! Registered Senior Member

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    Parthenogenesis can occur in human females. If a certain series of hormones is triggered, evan in the abstance of sperm an egg can still start developing. It is only hapliod, but it develops into a tumor that has hair and teeth. Freaky!
     
  10. Buckaroo Banzai Mentat Registered Senior Member

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    Before I read the conclusion I've thought for a second that the egg developed in a X0 person....
     
  11. 2inquisitive The Devil is in the details Registered Senior Member

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    I just came across this thread. Parthenogenesis is not all that uncommon reptiles, for
    instance, there have been several snakes in zoos which produced young without a
    male being anywhere around, ala Jurassic Park. I thought I remembered reading
    something fairly recently about a large mammal (can't remember what) that gave birth
    through parthenogenesis in a zoo, but I can't find a link, so I may be mistaken. I do
    have a link to the birth of bamboo sharks by parthenogenisis in a zoo. It was supposed
    to have happened with some other sharks in another zoo, also.
    http://news.nationalgeographic.com/news/2002/09/0925_020925_virginshark.html
     
    Last edited: May 26, 2004
  12. Buckaroo Banzai Mentat Registered Senior Member

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    Resurrecting one of my creations.....

    I think that what I first suggested as parthenogenesis wasn't really this, since it involves fertilization of an egg by a corpuscle, and not an unfertilized egg developing spontaneously. I don't know how it would be called though... anyway, recently I found this dubious site with somethings on "virgin birth":
    http://ourworld.compuserve.com/homepages/dp5/sex2.htm

    In this page is said that the parovarium (organ of Rosenm├╝ller) can produce sperm-like cells (they say "sperm"! not sperm-like...) that can fertilize her eggs. Anyone knows if that's true?


    About true parthenogenesis in humans this site says
    I don't know what "ibid" means, I guess that means that refers to the previous source of reference, but different pages....

    Researching through google I found that parthenogenesis really occurs in humans, but in anywhere but in this site I found that a parthenote embryo can develop completely as a fertylized embryo, rather parthenotes result in teratomas, what was cited few posts ago by Enigma'07. I've found that teratomas can have several specialized tissues and organs, such as glands and even eyes, but in a messed manner. Although there's a phenomena called fetus in fetu, which some people think that may be a highly organized teratoma, I think I've read something about a functional heart.

    This thing led me to think in a analogy for development, and I would like to know if this is valid, from someone expertised in this issues. Development would be like pulling, causing to fall a domino, triggering the fall of lots of dominoes organized in lines. Normal embryonic development, on fertilized eggs, would be like pulling the correct first domino piece; teratomas would be like pulling a domino on the middle of the way, causing to only a few of the pieces fall correcly, as planned.
    If this analogy is valid, seems that a tremendous luck could result in a fully-correct developed parthenote (excluding non-letal effects of monosmomy... if such thing really could happen)... or there's something more fundamental in the development of mammals that crucially needs fertlization (by a male, necessarily, or female self-fertilization would fit?)?
     
  13. hypatia Registered Senior Member

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    I think someone above mentioned this: the imprinting pattern has to be correct for viable offspring to result.

    That is, patterns of DNA methylation are different in male and female gametes. If a polar body were to fertilize an ovum (which sounds next to impossible, since it doesn't have the swimming and targeting machinery the sperm uses to find and fuse with the egg), the resulting embryo would have a double pattern of 'mom gene' methylation and no 'dad gene' methylation. I doubt it would be viable.
     
  14. Kumar Registered Senior Member

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    Can there be any possibilty of somewhat "self cloning"--a women get her own DNA to egg(if blank egg can be possible in natural way)? We sometimes see offspring matching exactly to either mother or father. If it can happen then women can only get a female baby.??
     
  15. Buckaroo Banzai Mentat Registered Senior Member

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    Update from the fan of the odd and the weird.
    Look what I've found:

    http://www.unc.edu/courses/2002fall/biol/122/001/Human%20genetics%20Dual%20identities_files/DynaPage(1).htm


    Kumar,
    I'm not sure about the self cloning part, I guess that as in the gametogenesis allways gets only half of the genotype, so an hipothetical parthenote could never be a clone of the mother.
    But in any instance that parthenogenesis occur, it only results in females, or at least in species in which females are determined by a pair of X chromossomes, or something like it.
     
  16. S.A.M. uniquely dreadful Valued Senior Member

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    Immaculate Conception?

    http://www.boston.com/news/science/articles/2007/06/25/shark_bite_leads_to_reproduction_mystery/

    Asexual reproduction in sharks?:confused:
     
  17. iceaura Valued Senior Member

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    I think mammals are just about the only major group of living beings that do not do this, ever.

    Might have something to do with the internal womb and placenta.
     
  18. Buckaroo Banzai Mentat Registered Senior Member

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    Back to this eerie subject again. Adding some stuff I think wasn't mentioned before:



    The last one states that homunculi have never been found with skeletal muscle, but another article reports such a case:





    I'm almost sure I've read once about instances where a normal non-parthenogenic zygote develops into a "normal" teratoma-like mess of unorganized tissues and organs. Anyone knows how it's called?
     
  19. draqon Banned Banned

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    this introduces fallacies in DNA replication...and the likelyhood that an offspring will be a mutant or have problems is quite high.
     
  20. Buckaroo Banzai Mentat Registered Senior Member

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    What is a "fallacy" in DNA replication?

    The zygote wouldn't be exactly a mutant, but would have increased risk of problems related with homozigosity, and as with true parthenotes, probably problems of low-viability due to lack of a complementary male pattern of DNA methylation.


    By the way, about the methylation subject, I've read in another forum someone suggesting that maybe a XXY woman could have this "solved". But I don't remember anything about this syndrome, I thougth that usually an abnormal number of sex chromosomes would result in sterility.

    And I also think that maybe, somehow, the gametogenesis may just keep with the individual woman's "normal" methylation pattern, as if it was just a regular somatic cell in this regard.
     

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