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36.1 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Mon Feb 24 1997 06:14 | 9 |
| >I heard on the news this morning that the English have "Cloned
>an adult sheep".
Bloody typical. It was the Scots who cloned the sheep. They took a
single cell from an adult sheep's udder and inserted this in into an
unfertilized egg. This was placed inside the womb of a sheep who
brought it to term. I will see if I can find the news story.
Jamie.
|
36.2 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Mon Feb 24 1997 07:12 | 57 |
| RTos 23-Feb-97 12:54
Scientists Claim First Clone of Adult Animal
Copyright 1997 Reuters Ltd. All rights reserved.
LONDON (Reuter) - British scientists said on Sunday they had created
the world's first clone of an adult animal in a breakthrough that
should provide a huge boost to work on aging, genetics and medicines.
The clone is a seven-month old sheep called Dolly, who was created at
Edinburgh's Roslin Institute from a single cell taken from the udder of
an adult sheep, turned into an embryo and then implanted in a surrogate
mother.
"What this will mostly be used for is to produce more health care
products. It will enable us to study genetic diseases for which there
is presently no cure and track down the mechanisms that are involved,"
the leader of the Roslin team, Ian Wilmut, told Britain's Press
Association news agency.
"The next step is to use the cells in culture in the lab and target
genetic changes into that culture," he said.
The technique could theoretically be used to clone humans -- as
foreshadowed in British author Aldous Huxley's "Brave New World" and
the film "The Boys From Brazil" in which clones of Hitler were made.
But British scientists say no responsible biologist would support such
work and it would be outlawed anyway by British laws covering embryo
and fertilization research.
"We are aware that there is potential for misuse, and we have provided
information to ethicists and the Human Embryology Authority. We believe
that it is important that society decides how we want to use this
technology and makes sure it prohibits what it wants to prohibit,"
Wilmut said.
"It would be desperately sad if people started using this sort of
technology with people," he added.
Britain's Observer newspaper said the breakthrough would make it
possible to genetically engineer sheep for the production of human
medicines, such as blood-clotting factors in their milk.
Scientists could also gain insights into aging by using the genes of an
old animal to make an embryo and study the way tiny genetic errors were
accumulated through age.
The Roslin team last year cloned sheep from cells taken from embryos
and cultivated in a laboratory.
Before now it had been thought impossible to perform the same operation
using cells from an adult animal, because an adult body is so much more
complex than an embryo.
REUTER
|
36.3 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Mon Feb 24 1997 07:13 | 102 |
| AP 23-Feb-1997 16:48 EST REF5027
Copyright 1997. The Associated Press. All Rights Reserved.
Researchers Clone Lamb
By MALCOLM RITTER
AP Science Writer
NEW YORK (AP) -- Researchers have cloned an adult mammal for the first
time, an astonishing scientific landmark that raises the unsettling
possibility of making copies of people.
Scientists slipped genes from a 6-year-old ewe into unfertilized eggs
and used them to try to create pregnancies in other sheep. The result:
A lamb named Dolly, born in July, that is a genetic copy of the ewe.
The feat opens the door to cloning prized farm animals such as cattle,
and should make it much easier to add or modify genes in livestock,
experts said.
It's also scientifically stunning. Researchers used DNA from the ewe's
udder cells, proving that mature mammal cells specialized for something
other than reproduction could be used to regenerate an entire animal.
Scientists had thought that was impossible.
Experts said the same technique might make it possible to clone humans,
but emphasized that it would be unethical to try.
"There is no clinical reason why you would do this. Why would you make
another human being?" said Ian Wilmut, one of the scientists who cloned
the sheep. "We think it would be ethically unacceptable and certainly
would not want to be involved in that project."
Carl Feldbaum, president of the Biotechnology Industry Organization,
which represents about 700 companies and research centers in the United
States and abroad, agreed.
"I can think of no ethical reason to apply this technique to human
beings, if in fact it can be applied," he said Sunday.
"The biotechnology industry exists to use genetic information to cure
disease and improve agriculture. We opposed human cloning when it was a
theory. Now that it may be possible, we urge that it be prohibited by
law."
A report of the sheep cloning will be published in Thursday's issue of
the journal Nature by Wilmut and colleagues at the Roslin Institute
near Edinburgh, Scotland, and others.
Before the new work, scientists had been able to take tissue from adult
frogs and create genetically identical tadpoles. But the tadpoles never
developed fully into frogs.
To do the sheep cloning, scientists took cells from the ewe's udder
tissue and cultivated them in a lab, using a treatment that made the
cells essentially dormant. They also took unfertilized sheep eggs and
removed the nucleus, the cells' central control room that contains the
genes.
Then they put the udder cells together with the egg cells and used an
electric current to make them fuse. The eggs, now equipped with a
nucleus, grew into embryos as if they'd been fertilized. The embryos
were put into ewes to develop.
The process was horrendously inefficient. Of 277 fused eggs, only one
led to a lamb.
Wilmut said he expects the efficiency to improve. Someday a dairy
farmer, for example, might make a few clones of cows that are
especially good at producing milk, resisting disease and reproducing,
he said.
A farmer wouldn't want entire herds of identical animals, because
populations need a diverse genetic makeup, he said. Without that
diversity, a lethal disease that struck one cow might wipe out all the
clones, too.
The advance will also provide a much more efficient way to insert genes
into livestock, Wilmut and others said. Inserted genes can be used to
make animals secrete valuable drugs in their milk, for example.
Scientists currently insert genes into fertilized eggs in a laboratory,
which is a very inefficient way to produce animals that use the genes
properly.
With the new technique, they could start with a virtually unlimited
supply of body cells from an adult animal, use a much more effective
lab technique to insert genes, identify cells that use the genes as
planned, and fuse them to eggs.
Wilmut and colleagues published research last year that suggested this
technique could be done by inserting genes in embryo cells. But body
cells from an adult are far more plentiful than embryo cells, making
the idea more feasible.
Caird Rexroad Jr., an animal gene expert for the federal Agricultural
Research Service in Beltsville, Md., called the new work historic for
showing that whole mammals could be regenerated from mature-body cells
other than sperm or egg.
|
36.4 | | SUPER::DENISE | unholy water.... sanguine addiction...2 silver bullets | Mon Feb 24 1997 15:30 | 5 |
|
wouldn't that pretty much take your role out of the picture,
guys?
the femi-nazis would just LOVE that.
|
36.5 | | JGODCL::BOWEN | Hopefully everything is now avai.. Oh Shit! | Mon Feb 24 1997 16:38 | 9 |
| Tut tut denise...
I should have thought that you'd seen enough Star Trek episodes to
know what happens if Cloning is used as the main method of
reproduction, I mean not even the BORG use it !
But there again Star Trek is all fiction isn't it ;-)
gerbil$rushing_home_for_STTNG
|
36.6 | | 45862::DODD | | Mon Feb 24 1997 17:19 | 18 |
| denise,
it pretty much takes the women out as well. Their role is reduced to
being a suitable nest in which to grow the egg. Wasn't that the premise
of "Hellstrom's Hive"?
After all the clone contains no genetic material from the woman who
grows the baby. At first it sounds interesting - one might choose to
put aside some genetic material from one's loved ones so that they
could be regrown if tragedy struck. But you wouldn't get a replacement
wife, you'd get a baby with the genetic make-up of your wife.
Then - would you get a person anything like the clone donor? Physically
maybe, mentally probably not. I grew up at a time when we didn't have
TV, video games, PCs, cars, etc etc. Would I turn out the same?
Absolutely not.
Andrew
|
36.7 | | SUPER::DENISE | unholy water.... sanguine addiction...2 silver bullets | Tue Feb 25 1997 13:49 | 12 |
|
andrew,
you really do know how to reduce things to bare bones.
even if a woman is considered a mere `nest' the need
for her still exists whereas the men...
this, i believe is the premise of the femi-nazis...
no men.
kevin,
me watch star trek?? you're being funny again, aren't you?
|
36.8 | | MOVIES::POTTER | http://www.vmse.edo.dec.com/~potter/ | Tue Feb 25 1997 14:00 | 4 |
| Nah, the gurlies still need people to mend their cars, fit plugs, all that
kind of stuff...
//atp
|
36.9 | | SUPER::DENISE | unholy water.... sanguine addiction...2 silver bullets | Tue Feb 25 1997 14:05 | 3 |
|
mr::POTTER,
mind if i post this in WOMANNOTES?
|
36.10 | | MOVIES::POTTER | http://www.vmse.edo.dec.com/~potter/ | Tue Feb 25 1997 14:22 | 6 |
| mr::POTTER,
mind if i post this in WOMANNOTES?
Go ahead...just make sure my name ain't on it anywhere :-)
//atp
|
36.11 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Tue Feb 25 1997 14:26 | 6 |
| Not only is the subject of cloning sheep making the news, it also seems
to be making the ewes.
Jamie,
Go to your room.
|
36.12 | | SUPER::DENISE | unholy water.... sanguine addiction...2 silver bullets | Tue Feb 25 1997 17:30 | 4 |
|
>groan<
next!
|
36.13 | | RIOT01::SUMMERFIELD | Sic Transit Gloria Mundi | Thu Feb 27 1997 15:17 | 7 |
| re .6
Ahh, but Ira Levin solved that problem in The Boys From Brazil. Simply
place the cloned sprogs in an anvironment as similar as possible to
that which the clonee developed in et voila, a modern bunch Hitlers.
Balders
|
36.14 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Thu Feb 27 1997 15:18 | 5 |
| >place the cloned sprogs in an anvironment as similar as possible to
ODE
Jamie.
|
36.15 | | SUPER::DENISE | unholy water.... sanguine addiction...2 silver bullets | Thu Feb 27 1997 16:39 | 2 |
|
shame on you, balders.
|
36.16 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Thu Mar 06 1997 07:09 | 84 |
| AP 5-Mar-1997 20:09 EST REF5923
Copyright 1997. The Associated Press. All Rights Reserved.
Chicken-Quail Mix Causes Uproar
By AMANDA COVARRUBIAS
Associated Press Writer
SAN DIEGO (AP) -- When is a chicken not a chicken? When it sings and
bobs its head like a quail, thanks to an experimental brain-cell
transplant.
In what sounds like something out of a B horror movie, Evan Balaban, an
experimental neurobiologist at the Neurosciences Institute in San
Diego, carried out the switch.
"The larger implications are what this will teach us about the
development of brain circuits that produce behavior," Balaban said
Wednesday. "It could eventually help people who have brain damage or
mental illness or even brain diseases."
His research on Plymouth Rock chickens and Japanese quail was published
Tuesday in the Proceedings of the National Academy of Sciences.
Although different from cloning, his work is adding to the furor over
genetic experimentation.
"This is more dangerous than cloning," Rush Limbaugh said on his radio
show Wednesday. "When the animal rights people get in on this, I might
join them."
But one ethicist said this experiment's implications aren't dangerous.
"This is a big week to hyperventilate about barnyard biotechnology,"
said Glenn McGee, director of research ethics at the University of
Pennsylvania. "But we've got to be careful not to overreact. It doesn't
mean that soon there will be armies of baby Ronald Reagans or Michael
Jordans."
Balaban does not see his work as opening the way for people with
socially unacceptable behavior being forced to undergo brain surgery.
"There's no good reason to do this in humans," Balaban said. "It's not
technically possible to do this in mammals anyway. There are some
enormous obstacles that would have to be overcome."
In the quail-and-chicken experiment, after much trial and error,
Balaban discovered that certain cells in the quail midbrain changed the
animal's sound patterns, and other cells in the quail brain stem
changed head movement during singing.
Balaban incubated fertilized quail and chicken eggs for 48 hours and
then cut tiny windows in their shells. Cells in the chicken embryo were
removed and substituted with corresponding quail brain cells.
Quail and chickens were used because each species has a distinctive
crowing and bobbing pattern.
Sound patterns and bobbing behaviors were documented on videotape in
experimental chickens that received quail brain cell transplants and in
a control group of chickens that received chicken transplants only.
The chickens were killed after 14 days to further document the results
with brain examinations.
Balaban's previous research, published in 1988 in the journal Science,
transplanted cells governing only the quail's sound pattern. No bobbing
measurements were done then.
"Evan can separate the sound and posture involved in crowing," said
Masakazu Konishi, a neurobiologist at the California Institute of
Technology in Pasadena. "That's new. That's interesting. It means
posture and sound that usually occur together in crowing are controlled
by different neuromechanisms."
Balaban's work continues a long line of research by neuroscientists who
are trying to understand cells and their connection to certain
behaviors.
"We know from transplant work done over the last 10 years that you can
never rewire or replace cells lost or damaged," Balaban said. "So if we
want to develop new therapies, we have to work with the cells still
left. It could have a good impact on some behavioral deficits."
|
36.17 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Thu Mar 06 1997 07:14 | 86 |
| AP 5-Mar-1997 19:20 EST REF5869
Copyright 1997. The Associated Press. All Rights Reserved.
Clone Fear May Slow Research
By PAUL RECER
AP Science Writer
WASHINGTON (AP) -- A Michigan congressman who is offering two bills to
ban human cloning research was warned Wednesday that a "rush to
legislate" could cripple biological studies that benefit medicine and
agriculture.
Rep. Vernon J. Ehlers, R-Mich., said he was introducing one bill that
would permanently ban federal funding of human cloning research and
another that would make it unlawful for anyone in the United States to
engage in such research.
Ehlers, a physicist, said the action would put legislative teeth into
an executive ban on federal funding of human embryo research that was
announced Tuesday by President Clinton. The president urged privately
funded labs to also refrain from human cloning experiments.
New laws are needed, Ehlers said, because "it is important for us to
draw the boundary."
The congressman described the bills during a hearing on cloning of the
House Science technology subcommittee. The witnesses included a group
of scientists led by Dr. Harold Varmus, the director of the National
Institutes of Health.
Washington concern over human cloning was prompted by the recent
announcement that a Scottish researcher had cloned a sheep, named
Dolly, from udder cells removed from an adult ewe. Shortly afterward,
scientists at the Oregon Primate Research Center announced that two
Rhesus monkeys had been cloned from embryo cells.
Ehlers said these recent developments have captured the interest of the
American public and there is worry that cloning could be misused.
Introducing legislation now, he said, could head off a groundswell of
public distaste that could cause a ban of all genetic research.
But Varmus urged Ehlers and Congress to proceed with caution in what it
forbids in biological research because some animal cloning or other
types of genetic manipulation can benefit humanity.
"Unless a bill puts a very tight fence around that which Congress wants
to forbid, it could cut off research toward a wanted goal," Varmus
said.
He said he believes Clinton's action on cloning "was intended to give
us a period of deliberation" and he urged Congress to wait until a
presidential group, the National Bioethics Advisory Commission, makes
its report in 90 days.
Dr. Thomas H. Murray, a member of the advisory commission, said,
"Before any irreversible action is taken, we need to be given 90 days
for public debate."
Dr. Caird E. Rexroad Jr. of the Department of Agriculture said his
agency's scientists have been cloning farm animals using genes from
embryos since 1986. This is different from the Scottish experiment that
produced Dolly using genes from an adult animal, he said.
Rexroad said the USDA is developing gene transfer techniques that will
produce animals that are low in fat and resistant to disease. Cloned
cows, he said, could produce more and richer milk.
James A. Geraghty, president of Genzyme Transgenics Corp., said his
company was using cloning techniques to make animals whose organs could
be used for human transplantation. Genetically altered cows or goats,
he said, could produce milk that contains drugs for the treatment of
human disease.
Dr. M. Susan Smith, director of the Oregon Primate Research Center,
said her researchers hope to use cloning techniques to produce a group
of identical monkeys that could be used to test drugs.
"Genetically identical monkeys would revolutionize the use of nonhuman
primates in biomedical research," Smith said. Fewer monkeys would be
needed and the drug studies would have a higher accuracy because there
would be no genetic differences between animals, she said.
REUTER
|
36.18 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Thu Mar 06 1997 07:15 | 72 |
| RTos 06-Mar-97 05:38
Scottish Researchers Escalate Cloning Plans
Copyright 1997 Reuters Ltd. All rights reserved.
LONDON (Reuter) - The scientists who created Dolly the sheep, the
world's first adult clone, said Wednesday they hoped to make a
genetically-manipulated clone that contained human genes by the end of
the year.
The researchers at Scotland's Roslin Institute and PPL Therapeutics Plc
also hope they can clone an adult cow by the end of the year.
"We expect to have transgenic clones within this year," Dr. Alan
Colman, research director at PPL, told Reuters. Such a clone would
contain human genes.
News that a sheep had been cloned using a cell from an adult sheep
shocked the world and prompted a flurry of soul-searching about whether
the technology was morally acceptable.
This week President Clinton banned federal funding of cloning and
German Research Minister Juergen Ruettgers called for a worldwide ban
on cloning human beings.
Danish scientists who were trying to produce cloned cattle said
Wednesday they were halting experiments pending a full debate on the
issue.
"We have stopped our attempt to transfer embryos using the technique
where the cells from an adult animal are included," Henrik Callesen,
director of the Foulum Embryo-Technology Center, told Reuters.
But the Roslin and PPL researchers say cloning is a natural outgrowth
of their research into animal breeding and the production of medicines
from animal blood and milk.
PPL already has non-cloned sheep that have partly human genes. The
transgenic sheep produce a human protein, AAT, that is now being tested
for use in treating cystic fibrosis.
The company also has a herd of cows in Blacksburg, Va., and is
attempting to clone them.
"It is still early days," Colman said. "There are no live-born Dollies
in the cow area."
But he hoped for a cow clone "quite late this year." Pig clones are
even farther down the road, he said.
Dolly may be a clone but she is not transgenic, since her genes are 100
percent sheep genes.
The point of the cloning is to be able to genetically manipulate cells
before the embryos are conceived in the test-tube, thus creating live
animals that have precisely the genetic characteristics that the
company wants.
For example, PPL would like to be able to more efficiently produce AAT,
since current ways of creating transgenic animals are hit and miss.
They can introduce the human DNA into a cell, but it only "takes" in
the animal cell about five percent of the time.
"What we actually want to do is create a successful cell and create a
clone of animals," Colman said. "We are hoping for an instant
production herd."
Cloning technology could also help researchers remove undesirable genes
as well as put genes in, Colman said.
REUTER
|
36.19 | | IJSAPL::ANDERSON | I feel all feak and weeble, doc | Thu Mar 06 1997 07:16 | 40 |
| RTw 05-Mar-97 21:46
Italy moves to ban animal and human cloning
Copyright 1997 Reuters Ltd. All rights reserved.
ROME, March 5 (Reuter) - Italian Health Minister Rosy Bindi said on
Wednesday human cloning should be outlawed and announced a temporary
ban in Italy on all forms of human or animal experiments linked with
cloning.
Bindi told a question time session in the Chamber of Deputies (lower
house) that a ministry commission was already working on a text to
present to Prime Minister Romano Prodi's centre-left government at a
cabinet meeting.
She said that because of the close relationship between animal and
human cloning, she had adopted an urgent ministerial measure lasting
for three months.
It outlawed "any type of experimentation or intervention, however it is
carried out, with the aim, even indirect, of human and animal cloning."
The controversial subject of human cloning hit the headlines last month
after scientists in Scotland introduced the world to Dolly, a lamb
cloned from an adult sheep.
Bindi said she was concerned that a lack of legislation on the subject
could lead to experiments with no guarantees of respect for public
health.
Germany on Wednesday called for a global ban on cloning humans and
Danish scientists, working like their Scottish and Australian
colleagues on cloning livestock, said they were halting experiments on
cows pending a full debate on the issue.
Bindi also announced a ban on all commercialisation of embryos or other
material related to artificial fertilisation.
REUTER
|
36.20 | | IJSAPL::ANDERSON | Spring has sprung! | Tue Mar 11 1997 07:09 | 76 |
| RTw 10-Mar-97 20:23
Public worried by risks of cloning, meeting told
Copyright 1997 Reuters Ltd. All rights reserved.
By Maggie Fox
LONDON, March 10 (Reuter) - Consumers are frightened about genetics
technology because they are being kept in the dark about developments
until they hit the marketplace, delegates to a biotechnology conference
agreed on Monday.
Ministers who addressed the conference agreed that Britain's extensive
system of review committees which examines issues of biotechnology and
genetic engineering was not enough to ease public fears about cloning
and genetically engineered food.
"Consumers are no longer prepared to accept blanket statements that
there is no risk," Alan Malcolm of the Institute for Food Research told
the conference.
News that scientists at Scotland's Roslin Institute had cloned a sheep
sent shivers around the world, with U.S. President Bill Clinton calling
for the National Biotechnology Advisory Commission to report on the
implications, and meantime tightening a ban on federal funding of human
clone research.
Several other governments and the European Union are also investigating
the implications of research.
EU battles are also underway over the import of genetically modified
soybeans and maize from the United States.
Robin Grove-Wright of the Centre for the Study of Environmental Change
at Lancaster University said trust was a problem.
"There is a major problem of public trust which has been exacerbated by
the recent BSE crisis," he told the conference. Government and industry
were seen as "operating mendaciously and against the public interest."
Grove-Wright presented a report his group did on public attitudes to
biotechnology.
"Fewer than half the participants had heard of biotechnology in the
context of food," the report read. Many people felt it was "unnatural"
and drew analogies with BSE, which scientists say arose from feeding
sheep's remains to cows.
"The development of genetically modified foods appeared to be seen as
lying outside people's control, with little sphere for public choice or
intervention. It was commonly seen as being dirven by powerful
financial interests," the report said.
Delegates agreed that Britain's complicated system of committees
discussing such issues, which includes the Human Genetics Advisory
Commission and the Human Fertilisation and Embryology Authority, was
not enough.
"The regulatory system alone cannot carry the burden of maintaining
public confidence. All those with an interest in the technology must
work closely together to achieve this," Environment Secretary John
Gummer said.
"I would like to see the industry adopt and develop effective voluntary
measures," Gummer told the 200 delegates, who included scientists,
experts from environmental and medical bodies and consumer groups.
"We have to keep the legislation ahead of the technology," David Fisk
of the Environment Department said.
He also said there should be more examination to ensure the technology
was as safe as companies said it was. "We need to look at the research
that is confirming our risk assessments."
REUTER
|
36.21 | | IJSAPL::ANDERSON | All that sheep tupping worked! | Mon Mar 17 1997 07:11 | 90 |
| RTos 16-Mar-97 18:59
Experts: Human Clones Wouldn't be Exact Copies
Copyright 1997 Reuters Ltd. All rights reserved.
WASHINGTON (Reuter) - As society debates the ethics of cloning,
scientists and ethicists say it is important to understand that cloning
a human being could never produce an exact duplicate.
Everything from the cytoplasm of the egg cell where the DNA genetic
blueprint is placed, to whether a cloned person remembered the Beatles
would impose individuality on "borrowed" DNA.
Even identical twins, who are nature's clones, are not totally
identical. Clones made in a laboratory would be twins born years or
decades apart, separated by generational and cultural chasms.
"By far the most mischievous misunderstanding is this idea that you can
Xerox people," said Harold Shapiro, president of Princeton University
and chairman of the National Bioethics Advisory Committee which
President Clinton has asked to evaluate the legal and moral dimensions
of cloning.
"If you lost a child or parent, and wanted to bring a person back --
you can't do that," Ian Wilmut, the scientist who cloned a sheep in
Scotland, told a U.S. Senate panel last week.
Many experts, including Wilmut, are deeply troubled by the idea of
cloning humans, a technology that could transform reproduction into
replication; that could turn a parent and child into a pair of
identical twins.
"If you take the DNA and, 20 years later, you put it in a different
uterus, you couldn't possibly replicate a person," said Harvard
University medical ethicist Lisa Geller.
"And if that's what you're trying to do, to replicate a person --
you're going to have a hell of a hard time with a teenager," she added.
Ethicists, geneticists, biologists and psychologists argue endlessly
about the balance of "nature" and "nurture" in human development, about
which traits are inborn and which are shaped from environment and
experience.
But even those experts tilting toward the "nature" end of the spectrum,
like psychologist Thomas Bouchard of the well-known University of
Minnesota Center for Twin and Adoption Research, say human clones would
look alike, but would not necessarily be alike.
"The difference in temporal experience would magnify the difference in
personality," said Bouchard, who believes about half of psychological
tendencies are inherited.
Environmental factors come into play from the very start. The cytoplasm
of the cell into which the DNA is placed will be different from the
adult cell from which it is derived. Small pieces of genetic material,
known as mitochondrial DNA, will also be distinct.
And once the clone is implanted into a womb, the prenatal environment
will differ as well. The diet of the woman carrying the fetus, whether
she smokes, what chemicals or toxins she encounters in her daily life
all affect the child.
"Identical twins are usually brought up roughly together, and treated
in similar ways. But if the clone and source differ by a generation ...
all kinds of things change over a generation, what's allowed, what's
taught, our diet," said Philip Kitcher, a philosopher at the University
of San Diego and the author of "The Lives to Come: the Genetic
Revolution and Human Possibilities."
A clone of Albert Einstein, taken out of 19th century Germany and
placed, for instance, in late 20th century southern California would
probably still be smart, and may well have the same wild white hair.
But he would not necessarily become a physicist.
A clone of Michael Jordanwould probably be tall, agile and have
lightning reflexes. But he might not become a professional basketball
player.
And a clone of any ordinary man or woman might look almost
indistinguishable from the genetic parent, but could have a whole
different view of the world, based on experience, luck or what
theologians would call soul.
"Dolly (the cloned sheep) is a snapshot -- not a snapshot of an adult
sheep but one of that sheep's cells," said University of Pennyslvania
bioethicist Glenn McGee.
REUTER
|
36.22 | | IJSAPL::ANDERSON | All that sheep tupping worked! | Thu Apr 10 1997 08:42 | 89 |
| AP 9-Apr-1997 14:52 EDT REF5744
Copyright 1997. The Associated Press. All Rights Reserved.
Cloning Explained
By PAUL RECER
AP Science Writer
WASHINGTON (AP) -- Dolly, the Scottish sheep that is the first mammal
cloned from an adult, is a biological confusion to most Americans. A
primer on what cloning is and what it's not:
--Cloning is not creating an instant carbon copy adult human from
another adult.
That is impossible. A cloned adult would have to go through the same
development -- from gestation and birth through childhood to adulthood
-- as do all other humans.
To clone a 40-year-old adult would take 40 years, plus nine months. By
the time the clone was age 40, the original adult would be almost 81.
They would be like twins separated by four decades.
And the clone would be only a genetic copy. Much of what shapes
personality and character are the mental and emotional effects of
nurturing, culture, education and luck. These are too imperfectly
understood to be duplicated from one generation to another.
--Cloning is reproducing without sex.
Natural reproduction among mammals involves a union of sperm from the
father and egg from the mother. Both the sperm and the egg carry genes.
When these unite, they result is a genetically unique individual. It
may bear resemblance to one parent or another, but it is not precisely
like either.
In cloning, the embryo gets all genes from one individual. In Dolly's
case, all of her genes came from a 6-year-old adult ewe.
The process, though, required the help of two other female sheep. From
one sheep, researchers removed an egg and took out the nucleus, the
master control center that includes the genes.
From the 6-year-old ewe, the researchers then took a mature udder cell
and removed the nucleus, including the genes. The nucleus was put into
the enucleated egg from the first ewe. Lab manipulation caused the egg
and transplanted nucleus to develop into an embryo. This was then
placed into the uterus of a third ewe, which later gave birth.
The result, Dolly, has the genes from one ewe nurtured in the egg of a
second ewe, and born to still another ewe.
There was no male, or father, involved. Dolly's genes match those of
the 6-year-old ewe that contributed the udder cell. The other two ewes
have no genetic relationship with Dolly.
--Cloning is not easy.
Researchers at the Roslin Institute in Scotland tried 277 times before
they produced Dolly.
Along the way, a number of defective lambs died shortly after birth.
There were also scores of embryos spontaneously aborted.
Ian Wilmut, the lead scientist, said that is a main reason he believes
cloning is not for humans: There is a risk of producing babies with
monstrous defects.
--Cloning's technology could have valuable uses.
By precisely controlling genes, farm animals could be made to produce
more milk, meat or wool.
Manipulating genes could cause milk from goats and cows to produce
pharmaceutical proteins -- medicines that can cure. Once such animals
were created, cloning would allow science to make huge herds of walking
drug plants.
Dr. Harold Varmus, director of the National Institutes of Health,
argues that cloning also holds the promise of learning how to turn
genes on and off. That would mean human genes could be made to produce
new tissue for the repair of old or diseased tissue: skin for burn
patients, new limbs for severed ones, new bone marrow for cancer
patients.
All would use only a few genes and would not require the making of a
cloned human.
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