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Okay some dumb questions!!When they freeze a womens egg they do it so she can get pregnant later on right?
Whats the difference between an embryo and an egg? Is an embryo a fertile egg? Which one do they freeze?
Is a stem cell a fertile egg?
Do they take out the dna of a fertile cell and insert a person's own dna to grow body parts?
Does anyone know whats happening here or am I just to stupid to figure it out?......Kirk
-- Anonymous, December 20, 2001
Hi Kirk, having undergone years of unsucessful fertility treatments, I know a few of the answers to your questions.Yes, they freeze women's eggs for future use, by her, or as an egg donor for women like me who has defective eggs.
An embryo is a fertilized egg that has undergone 3 to 4 days of "growing" and dividing, they are relatively unsucessfull with freezing anything any farther along than that.
A stem cell can be taken from umbical (sp.?) cord blood, embryonic tissue, as well as from living adult tissue, it does NOT have to be taken from fetal and embryonic tissue. Stem cells are so desirable because they can become most any type of body tissue, they are the original all purpose body cell producer, much like duct tape in a handy man's tool kit.
DNA is taken out of any cells nucleus and the donor's replaced in it to try to "grow" body parts, so far, no luck. The best luck has been achieved so far with replacing DNA in the donor egg's nucleus with the animal to be cloned DNA. They replace all the genetic material in the donor egg's nucleus with the replacement DNA, so far, not just part of it.
The sucess rate for mammalian cloning is one sucess in 350, with many, many genetic "accidents" happening, and not surviving until live births.
I can't see human cloning happening sucessfully for another 50 years at least, nor do I approve of it for moral and ethical reasons, but I do approve of "replacement parts" being grown from adult stem cell donor cells, not fetal or embryonic research.
-- Anonymous, December 20, 2001
I can't see human cloning happening sucessfully for another 50 years at least, nor do I approve of it for moral and ethical reasonsWow, 50 years! I'm no expert on the subject but I would guess that cloning of humans will be a regular occurance within 10 years. It just seems that the way technology is advancing, 50 years seems like an eternity... :-)
Annie, I'd be interested in hearing your thoughts on why you believe cloning humans is immoral or unethical. The only instances where I could see it being unethical or immoral is if the cloned individual would be used as a supplier of body parts or if the process of cloning hadn't been perfected and we were creating damaged or unhealthy clones.
But if cloning is used to allow childless people to have children - and the technique for cloning has been "perfected" - then I guess I really don't have a problem with it.
-- Anonymous, December 20, 2001
So a fertile egg (embryo) has split into cells that have stem cells that are the most sucessful in cloning? That right? Is that the problem with the (right to life people) because the success has been only with fertile cells?.....Thanks Kirk
-- Anonymous, December 20, 2001
Jim-Bob, if they could clone humans without using literally hundreds of human embryos, and trashing those precious bits of human life as so much material that is wasted in the cloning process, then, yes, I would have absolutely no problem with the moral and ethical aspect of cloning. But, we are not even close at getting that kind of sucess rate, I'm talking a one egg or two egg attempt, like that occurs in Nature in normal embryonic development, not 350 embryos trashed.It's all those unborn embryos that trouble me, the type of society that would allow that to continue without questioning it existed in Hitler's reign of terror, human life is a precious thing that has insintric (sp.?) value, not some that is to be devalued in our futile modern cloning attempts.
I went through much the same debate with my ob/gyn in our fertility treatments, the doctor pushes multiple embryo production and subsequent transplant, but I told him I would only approve of multiple egg production, and allow natural fertiliztion or I.F. to occur, the number of surviving embryos would NOT be "selectively reduced" if the procedure was successful. I considered this the only moral and ethical way to approach this enigma.
Kirk, stem cells can be obtained from most any living tissue, it's just that they are most easily obtained from embryos and umbical tissue, but it is not necessary to get stem cells that way at all. Just cheaper and easier.
-- Anonymous, December 20, 2001