FW: Parthenogenesis!

[Tim Gwinn <***>]

Forwarded on behalf of Judith Rosen.   Regards, Tim   (Replaced .GIF image dividing line in article w/HTML horizonal line -TG)   -----Original Message----- From: Judith Rosen [mailto:*** Sent: Thursday, December 02, 2004 3:33 PM To: Tim Gwinn Subject: Fw: Parthenogenesis! Tim, the list wouldn't accept this one, either. Would you mind posting it for me? ----- Original Message ----- From: Judith Rosen To: Robert Rosen discussion Sent: Thursday, December 02, 2004 2:32 PM Subject: Parthenogenesis! This just came into my "in-box" from NewScientist... It's one of those moments of deja vu where something from the past that was ahead of its time is now realized...   Among the fiction I've written is a short story, called "A Feminist's Nightmare": A futuristic, comedic/philosophical sci-fi story that begins at the point in human history where the "Y-gene" has recently died out of the human gene pool. The story is set a few centuries from now, and global warming has caused a lot of trouble in the centuries between now and the beginning of the story. The main plot device is that viable frozen sperm have just been discovered in an insulated containment system found by an archeology team in an abandoned Antarctic human colony underground. There are overtones of "divine intervention" and virgin births, etc, which are either part of the comedy or part of the philosophy, depending on the reader, I guess, but in the story, the world has to decide whether, and how, to attempt repopulating the Y-gene into the human gene pool. In other words: should we try to get men back or shouldn't we? (hence the title)...    The way reproduction was handled by this single-gender version of humanity was partly responsible for the loss of the Y-gene: Parthenogenesis. In the story, the technology was initially developed to deal with widespread male infertility caused by environmental degradation and diseases. I got the idea for this story while traveling with my father in the late 1980's and I checked with some of his colleagues who were involved in medical research as to whether this idea could work. I was told that "Well... it SHOULD be possible..."   My idea was that if you zapped a human egg and got it to reverse meiosis, it would have the full complement of genes just as a fertilized egg would; the second set of genes would be a mirror version of the first. This is very different from cloning although ultimately, if enough generations of women reproduced this way in succession, mothers and daughters would be genetically identical except for random mutations. In the first generation, though, a brown-eyed, dark-haired woman could have a baby with blue eyes and blond hair-- if those genes are in her gene pool. One little side effect: All babies would be female.   So here's this article from NewScientist The way they describe their process is kind of surprising to me. Does anyone on the list know about this "shadow set of genes"?:

The World's No.1 Science & Technology News Service Zapped human eggs divide without sperm 19:00 01 December 04 Exclusive from New Scientist Print Edition. Subscribe and get 4 free issues. A trick that persuades human eggs to divide as if they have been fertilized could provide a source of embryonic stem cells that sidesteps ethical objections to existing techniques. It could also be deployed to improve the success rate of IVF. ?Embryos? created by the procedure do not contain any paternal chromosomes ? just two sets of chromosomes from the mother ? and so cannot develop into babies. This should remove the ethical objections that some people have to harvesting from donated human embryos. There are high hopes that stem cells, which can develop into many different cell types, could be used to treat a range of diseases. The tricked eggs divide for four or five days until they reach 50 to 100 cells ? the blastocyst stage. These blastocysts should in theory yield stem cells, but because they are parthenogenetic ? produced from the egg only ? they cannot be viewed as a potential human life, says Karl Swann of the University of Wales College of Medicine in Cardiff, UK. ?This could eliminate one of the main sources of ethical controversy in this research,? says Bob Lanza, head of research at the cloning company Advanced Cell Technology in Worcester, Massachusetts. But Josephine Quintavalle of Comment on Reproductive Ethics, a London-based pro-life lobby group greeted the new procedure with caution. ?I?d be happier if it was beyond all reasonable doubt that it could not become a human life.? She added that women must not be exploited to provide eggs. ?Spark of life? Swann?s team tricked the eggs into dividing by injecting phospholipase C-zeta (PLC-zeta), an enzyme produced by sperm that Swann discovered two years ago with Cardiff colleague Tony Lai. ?It?s the spark of life,? says Swann, who has previously showed that the human version of the protein can trigger mouse eggs to develop into blastocysts. ?It tricks the egg into thinking it has been fertilised.? Human eggs contain two sets of chromosomes, one of which is normally jettisoned within two hours of fertilisation. Swann and his team used a standard chemical treatment to prevent this, so both sets in the parthenogenetic embryos come from the mother. The embryos appear to undergo the same changes as naturally fertilised eggs, producing waves of calcium ions across the cell every 20 to 30 minutes.