Several
animal species have already been genetically modified, and at
least eleven have been cloned, though some scientists doubt the
health of those clones that survived to birth.
Some of these efforts are commercial, either for agribusiness
or for sale directly to consumers as pets. Others are scientific
experiments, usually defended as advancing, directly or indirectly,
the cause of medicine for humans.
The cloning or genetic modification of pets serves no justifiable
purpose. These efforts serve only to play upon one set of emotions-our
affection for our companion pets-in order to desensitize another
set of emotions-our repugnance at the idea of treating them
as artifacts that can be "designed" and manufactured.
The modification of livestock and the possibility of cloned
meat entering the food chain are very controversial. So is the
possible use of genetically modified animals to "grow"
either pharmaceutical products or organs for transplant into
humans.
Cloning
There have been published reports of the following species
being cloned: carp, sheep, mice, cattle, goats, pigs, cats,
rabbits, mules, horses, rats, and a deer. Some closely related
species have also been cloned (a banteng, a wild cow, and a
mouflon, a kind of sheep). A gaur, a wild ox, was cloned but
died within two days.
Attempts have also been made, without success, to clone monkeys,
dogs, pandas, chickens, and at least two extinct species: the
Tasmanian tiger and the woolly mammoth. The mammoth experiment
used an elephant surrogate and tissue found in permafrost.
Three major British institutions announced in July 2004 that
they were setting up a tissue bank to preserve the DNA of endangered
species, even after their extinction. Future cloning is seen
as a possibility.
The Roslin Institute, where the first mammal was cloned, maintains
records of all published mammalian cloning experiments up to
July 2002 - 50 papers detailing 68 experiments, with 386 surviving
clones. They conclude that the "overall efficiency of cloning
is typically between 0 and 3% (number of live offspring as a
percentage of the number of nuclear transfer embryos), irrespective
of the species, the donor cell type or technique." There
is no evidence that efficiency has significantly improved since.
Cloning for livestock
About 300 bulls have been cloned, with the aim of improving
the quality of breeding stock. Cloning is too expensive, at
around $20,000 per bull, to clone directly for meat, but breeding
bulls are worth much more than that.
The meat and milk of cloned cattle is presently kept off the
market pending FDA approval. Nevertheless, BIO is actively promoting
the use of cloned and transgenic animals for human food, as
well as for pharmaceuticals.
The FDA is investigating the possibility of selling meat from
cloned pigs as well as cattle, and in 2003 released a draft
executive summary well in advance of the report it was supposed
to summarize. "The FDA wants to gauge public reaction to
the prospect of food from cloned farm animals before it decides
whether to require government approval of the products before
they are sold. That decision is expected to take another year."
Pet cloning
In 1998 Arizona billionaire John Sperling gave $3.7 million
to Texas A&M University to clone his pet dog, Missy (the
"Missyplicity Project"). Sperling is controversial.
He became wealthy as founder of the University of Phoenix, a
distance learning university that has been accused by many of
being a "diploma mill." He has since used his assets
to support a number of idiosyncratic endeavors.
The dog-cloning effort failed, and the team, reportedly against
Sperling's wishes, began parallel efforts to clone a cat. The
birth of the first cloned domestic cat was announced by the
Texas A&M research team in February 2002. Born on December
22, 2001, "CopyCat" or "CC" was produced
by fusing an ovarian tissue cell from an adult cat with a cat
egg, and implanting the clonal embryo into an adult cat. This
cloning "success" occurred after 188 failed attempts.
Sperling retained Lou Hawthorne, a publicist from Marin County,
California, to handle public relations for his dog-cloning effort.
Hawthorne subsequently established "Genetic Savings &
Clone" as a profit-making venture to provide pet cloning
services
The company is offering to clone cats for $50,000. They also
offer "gene banking" services for up to $1395, plus
up to $150/year, all of which can be credited against the future
cost of cloning. They announced in April 2004 that five customers
had paid the fee, work had already begun on three other cats
for staff members and one more slot was available, to make "nine
lives."
They hope to increase production to several thousand a year,
and to reduce the cost substantially.
Genetic Modification
Science, mice, and patents
The most commonly genetically modified animal is almost certainly
the mouse. It is small, short-lived and sufficiently similar
to humans to be an almost ideal laboratory animal. As a result,
mice have not only been cloned and modified, they have led to
an actual industry in the production of "knockout mice,"
that is, mice with a particular gene or set of genes inactivated
for research purposes.
Trans Genic Inc asserts, "Currently, we are able to produce
almost 1,000 strains of Knockout mouse in a year."
"Pharming"
Cattle, sheep, goats, chickens, rabbits and pigs have been
genetically modified with the aim of producing human proteins
that are useful, generally as medicines. The gene transfer process
is typically very inefficient, and cloning is seen as another
way of propagating the GM animal.
A 1999 USDA report cited estimates that there was a $24 billion
market for human proteins, and theoretically 600 transgenic
cows could supply the worldwide demands for some drugs. In practice,
however, several companies that have pursued this line have
gone bust, and the profit potential seems less than it once
did.
Genetic modification of animals in order to improve the prospects
of organ transplants is also being investigated.
Genetically modified fish as pets
A tropical fish genetically modified to glow in the dark went
on sale in Taiwan in 2003 for about $17 each. A different variety
of zebrafish, called "GloFish," which were created
in Singapore, reached the United States market in January 2004.
The distributor says that GloFish were originally developed
to fluoresce only in the presence of pollutants, but that is
not the form in which they are being sold. They cost about $5
each, and are intended to live in aquariums, but can breed and,
in the right conditions, live in the wild.
The Food and Drug Administration (FDA) approved the sale without
ceremony. A coalition led by the Center for Food Safety filed
suit against the decision, but sales went ahead. In California,
the Fish and Game Commission initially banned the fish but later
agreed to hold hearings at the request of the distributor.
Allergy-free cats?
A company called Transgenic Pets, in Syracuse, NY, was widely
reported in 2001 to be working with scientists at the University
of Connecticut to "remove the allergen gene" from
cats. The company hoped to raise $2 million and sell the modified
animals for $1,000 each. Funding problems ended the project.
Genetic modification for aquaculture
Most discussion of bioengineered food focuses on plants, but
work on animals and fish is well under way. Genetically modified
salmon have already been created, though FDA approval is not
expected before at least 2006 and the target date has repeatedly
been delayed. The Biotechnology Industry Organization (BIO)
and the developers, Aqua Bounty Farms, claim that the GE salmon
grow faster but not larger than ordinary salmon, but this is
strongly disputed. Opponents also cite studies showing dramatic
population crashes and unpredictable environmental impacts.
Salmon are not the only fish species being modified. Acting
FDA Commissioner Lester M. Crawford summarized the position
in a speech given in March 2004:
"Less well known is that catfish and tilapia have been
also genetically modified to grow faster and more efficiently
than their non-transgenic counterparts. Rainbow trout has
been engineered to increase its contents of omega 3 fatty
acids, and shellfish is being modified to reduce its allergenicity
and make it grow faster."
The matter-of-fact, if not approving, tone of these comments
is disturbing, as it comes from the head of the agency that
is supposed to be regulating these technologies.
Other countries, including Canada, have moved much faster than
the United States to ban or at least place a moratorium on the
genetic modification of fish. Malcolm Grant, Chair of the UK
Agriculture and Environment Biotechnology Commission, points
out that
"Once the fish has escaped, there's virtually nothing
that can be done to recall it... Genetic biotechnology
has opened a new chapter in the relationship between man and
animals. We must therefore prepare now for developments that
may be many years away."
He also argues that pet cloning is "trivial, distasteful
and could be sold to gullible owners."
Genetically modified farm animals
Acting Commissioner Crawford continued:
"Cows can be bioengineered to produce several varieties
of milk: milk with a lower level of a protein that's allergenic
to some infants; milk that is more easily digested by people
who are lactose intolerant; milk that has more naturally occurring
antimicrobial enzyme, and therefore has longer shelf life;
and milk that makes better cheese because it has altered distribution
of caseins or less fat."
Genetic modification for livestock
Research is also underway to use genetic modification to improve
the health of cows and pigs. Advocates hope to produce cattle
that would be resistant to Mad Cow disease, for example.
There have also been reports of cows being genetically modified
to "produce milk with higher than normal levels of protein,
which would speed the process of making cheese."
Chimeras
Some researchers have created embryos with genetic material
from both a human and an animal, also known as chimeras. Most
claim this is for research purposes only, and such embryos would
never be implanted or brought to term. But some bioethicists
are unwilling to draw a line that would prevent it. For example,
Jason Scott Robert and Francoise Baylis assert that they take
"no stance at all" on whether "interspecies hybrids
or chimeras from human materials should be forbidden or embraced."
But much of their article is devoted to their contention that
"the arguments against... creating novel part-human beings... are
largely unsatisfactory."
The prospect of such human-animal chimeras being born raises
a number of troubling questions. Does such an organism have
human rights? What if it were 99.9% human and 0.1% chimpanzee?
What of the reverse situation?
The mixing of species can occur at three different levels.
First, some DNA from one organism can be inserted into another
organism's genome. Most often, however, these are described
as transgenic animals rather than chimeras. For example, scientists
have produced transgenic mice which contain some human genes.
Another type of chimera involves a blastocyst containing components
from multiple species. James Grifo has used this technique for
fertility research. After the US federal government informed
him he could no longer continue his experiments, his team moved
to China. There, they removed the nucleus from a fertilized
rabbit egg and inserted a nucleus from a human somatic cell.
The resulting embryos, which still contained rabbit mitochondrial
DNA, were allowed to grow for 14 days before destruction.
Finally, scientists have placed cells from one species, typically
human stem cells, into a multicellular embryo of another species.
In 2004, researchers were surprised to discover that injecting
human stem cells into a pig embryo resulted in a fetus whose
cellular components were intermingled down to the genetic level.
Many cells contained chromosomal DNA of both pig and human origin.
Opposition
Several environmental and animal rights organizations have
expressed opposition to pet cloning, including Friends of the
Earth and the Humane Society of the United States, the largest
animal welfare organization in the country.
Jeremy Rifkin from the Foundation on Economic Trends and Stuart
Newman of the New York Medical College and the Council for Responsible
Genetics have pursued a novel path of opposition. They filed
a patent application with the US Patent and Trademark Office
for chimeric embryos and animals containing human cells. They
did not intent to create a "humouse." Instead, they
tried to force the PTO to take a position and, if the patent
is granted, to prevent chimeras from being developed. |