Re: Great news for man haters. Sorry not decades earlier for those here
- From: toci <gina39d@xxxxxxxxx>
- Date: Thu, 26 Jun 2008 06:56:26 -0700 (PDT)
On Jun 26, 8:44 am, jim <jim10...@xxxxxxxxx> wrote:
http://docinthemachine.com/2007/04/13/allfemalebaby-2/
Scientists report today on the ability to create sperm from bone
marrow cells. Initially performed in men, the technique could
potentially be performed in women and lead to a sperm cell made from a
woman’s body. You got it right- that cell could then fertilize an egg
leading to the first female-female conception in human history.
As a fertility specialist I couldn’t resist this story and wanted to
share the reality and the hype. Prof. Karim Nayernia, Professor of
Stem Cell Biology at the Instatute of Human Genetics at the Univeristy
of Mewcastle on Tyne led the project reported in Biology of
Reproduction. A summary of the study was released in the Independent
today.
The researchers said they had already produced early sperm cells
from bone-marrow tissue taken from men. They believe the findings show
that it may be possible to restore fertility to men who cannot
naturally produce their own sperm.
But the results also raise the prospect of being able to take
bone-marrow tissue from women and coaxing the stem cells within the
female tissue to develop into sperm cells, said Professor Karim
Nayernia of the University of Newcastle upon Tyne.
The report suggests that “Scientists are seeking ethical permission to
produce synthetic sperm cells from a woman’s bone marrow tissue after
showing that it possible to produce rudimentary sperm cells from male
bone-marrow tissue.”
The Two Mommy- No Daddy Baby Making Research Plan:
“Theoretically is it possible,” Professor Nayernia said. “The
problem is whether the sperm cells are functional or not. I don’t
think there is an ethical barrier, so long as it’s safe. We are in the
process of applying for ethical approval. We are preparing now to
apply to use the existing bone marrow stem cell bank here in
Newcastle. We need permission from the patient who supplied the bone
marrow, the ethics committee and the hospital itself.”
If sperm cells can be developed from female bone-marrow tissue
they will be matured in the laboratory and tested for their ability to
penetrate the outer “shell” of a hamster’s egg - a standard fertility
test for sperm.
“We want to test the functionality of any male and female sperm
that is made by this way,” Professor Nayernia said. But he said there
was no intention at this stage to produce female sperm that would be
used to fertilise a human egg, a move that would require the approval
of the Human Fertilisation and Embryology Authority.
This same group reported last year that they created artifical sperm
from embryonic sperm cells in mice.
(They) isolated stem cells from blastocysts, which are early-stage
embryos only a few days old. From these cells were extracted those
that would go on to form sperm, known as spermatogonial stem cells
(SSCs). The SSCs were then cultured in the laboratory, and when some
developed into sperm, they were injected into female mouse eggs and
grown into early-stage embryos. The embryos were transplanted into the
wombs of surrogate mothers.
The Genetic Disaster That Could Result: Faulty Imprinting. There is a
huge genetic time-bomb here. The genetic phenomenon called imprinting.
This describes the situation where a particular gene is marked or
imprinted with a tag that says if it came from the mother or father-
and more importantly only one of the other is active. For example for
a particular gene it’s possible that only the maternal copy gene could
be active and the copy that comes from the mother could be switched
off. If this process goes wrong (mom and dad copy mistakes) then
severe genetic diseases can result.
A description of imprinting follows and a detailed description is here
and here
However, it is now known that the expression of a small number of
the 30,000 or so genes in the cells depends on whether the gene copy
was passed down from the father or the mother. This process, whereby
the expression of a gene copy is altered depending upon whether it was
passed to the baby through the egg or the sperm, is called imprinting.
The term “imprinting” refers to the fact that some chromosomes,
segments of chromosomes, or some genes, are stamped with a “memory” of
the parent from whom it came: in the cells of a child it is possible
to tell which chromosome copy came from the mother (maternal
chromosome) and which copy was inherited from the father (paternal
chromosome). This expression of the gene is called a “parent of origin
effect” .
- -
"Lenin called them "useful idiots," those people living in liberal democracies
who by giving moral and material support to a totalitarian ideology in effect
were braiding the rope that would hang them. Why people who enjoyed freedom and
prosperity worked passionately to destroy both is a fascinating question, one
still with us today. Now the useful idiots can be found in the chorus of appeasement,
reflexive anti-Americanism, and sentimental idealism trying to inhibit the necessary
responses to another freedom-hating ideology, radical Islam."
Bruce C. Thornton
Professor of Classics
American University of Cal State Fresno
Don't we really need more female hamsters? Toci
.
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