From: rhinoceros (rhinoceros@freemail.gr)
Date: Thu Jul 03 2003 - 12:06:24 MDT
Transexual human embryo created
http://news.bbc.co.uk/2/hi/health/3036458.stm
<snip>
In experiments using donated embryos, scientists from the Centers for Human Reproduction in New York and Chicago investigated whether healthy cells from one embryo could be implanted into a second defective embryo.
They found that, in some cases, the introduced cells do proliferate and spread throughout the chimaeric embryo.
Their hope is that having even a small proportion of cells from a healthy embryo might prevent certain genetic diseases from arising.
The "merged" embryos were never intended to develop into children, and were destroyed after a few days.
<snip>
The potential for cells from two different embryos to fuse and become one "combination" individual is well known in nature - there have been examples where this has happened in early pregnancy in humans, with no apparent ill-effects on the resulting baby.
The theory behind Gliecher's work is that some studies have suggested that in certain diseases caused by a single genetic defect, having even as few as 15% of the body's cells free from the defect might be enough to stop the development of the disease.
He said his experiment showed that just a couple of cells injected into the embryo produced an embryo with, in many cases, an even distribution of cells carrying these new genes.
He deliberately injected a male cell into a female embryo - which created an "intersex" embryo, but allowed him to use chemical tests to check the process of the chromosome unique to male cells.
<snip>
Professor Alan Trouson, a pioneer of IVF in Australia, told BBC News Online: "I really can't see the logic of what he is trying to do - it seems completely flawed to me."
He said that it would be impossible to test whether the correct versions of the genes had been incorporated widely into the embryo before a decision had to be made whether to transfer it back into the woman.
He said that the health risks of producing a chimaeric individual were still uncertain.
"Unless you can be certain you are doing some good, you should not be doing something that could cause harm."
He said that the US team should not even attempt to continue their experiments in animals.
Professor Lyn Fraser, a past president of the society, told the BBC that she shared the disquiet over the technique.
She said: "I don't see how it can be used to treat single gene disorders. It's hard to accept what they have done at all."
---- This message was posted by rhinoceros to the Virus 2003 board on Church of Virus BBS. <http://virus.lucifer.com/bbs/index.php?board=54;action=display;threadid=28786> --- To unsubscribe from the Virus list go to <http://www.lucifer.com/cgi-bin/virus-l>
This archive was generated by hypermail 2.1.5 : Thu Jul 03 2003 - 12:06:56 MDT