Cloning Cows

Cloned cows in US produce human antibodies   August 2002 - New Scientist

Cloned Cells Make Kidneys in Cattle June 2002 - Reuters

Bull Clone Stumps Brazil Scientists Expecting Cow - May 2002 - Reuters Scientists Clone Calf From Dead Cow April 2002 - Reuters Breakthrough they say will allow cattle producers to select and clone the choicest beef from their stock

University of Georgia Clones Eight Calves

June 27, 2001 - Reuters - Athens, Georgia

University of Georgia scientists have cloned eight calves using a technique they say can markedly improve the success rate of cattle cloning.

Steve Stice, lead scientist for cloning research at the university in Athens, about 60 miles northeast of Atlanta, said the technique involved the way cells from the breeder animal's DNA were handled.

``Before we used them in the cloning process, we treated them in a different way and made them more consistent, more homogeneous,'' Stice told Reuters late on Tuesday.

``Using a more consistent source material for cloning, it is our belief that we produced more viable embryos.''

Stice did not give more details on the technique, saying the school has applied for a patent. He said the method addresses a common problem in cloning: producing viable animals from cloned embryos.

In a March article in the journal Science, scientists who in 1997 created Dolly the sheep, the world's first cloned mammal, said procedures that have been used in cloning animals tend to yield a very low percentage of viable embryos, with many dying soon after birth.

But Stice said the University of Georgia's eight, full-term calves, ranging in age from 2 to 4 months, showed the success rate can be improved. He said the calves, which have identical genetic makeups, are clones of a cow that had grown too old to reproduce.

One of the calves was cloned using a combination of the university's technology and that developed by the company that produced Dolly the sheep, the researchers said.

In cloning, an egg's DNA is removed and replaced with the DNA of an adult cell. Mice, dairy cows, goats and pigs are among the mammals that have been cloned since Dolly.

Stice said he was optimistic the university's technology could enable researchers to duplicate the genetics of healthy animals to produce meat for consumption that is more consistent in taste and quality.

Scientists could ``find animals out there that are more resistant to certain diseases such as mad cow and hoof-and-mouth disease and then be able to clone those and spread those genetics much faster than traditional techniques,'' Stice said.

Endangered species cloned

October 8, 2000 - BBC

Reports from the United States say scientists have, for the first time, cloned an endangered species by using the eggs and the womb of another animal - a cow.

According to the Washington Post newspaper, an Asian gaur - a humpbacked, ox-like animal native to India and Burma - was cloned from a single skin cell taken from a dead gaur.

Scientists fused the cell to a cows' egg, whose own genes had been removed, then transferred it to the womb of another cow.

The baby gaur, already named Noah, is due to be born next month.

Giant pandas

The paper says the same team, from biotechnology company Advanced Cell Technology (ACT) in Massachusetts, is already considering cloning giant pandas.

The closest related species to giant pandas are rabbits and racoons but neither are ideal as potential surrogate mothers because of their size.

The company says it hopes to use captive black bears if they gain access to panda cells from China.

Officials at China's National Zoo, said on Friday they were always open to new ideas but had no plans at present to provide giant panda tissue.

Back from the dead

Later this year, the Washington Post reports, ACT intends to revive an extinct species of Spanish mountain goat called bucardos.

The last known bucardos died nine months ago, but some of the animal's cells were preserved.

Normally, a clone shares all the genetic characteristics of the original cell, including sex, which means a breeding population cannot be created.

But the ACT team hopes to gain permission from the Spanish authorities to use the latest molecular techniques to insert male chromosomes from a closely related goat species, creating male as well as female bucardos.

Cloned dairy cow born at University of Tennessee

Aigist 30, 2000 - AP

University of Tennessee researchers have announced the birth of a cloned dairy cow using a quicker and less complicated method than the method used to clone Dolly the sheep.

The researchers said Monday that a brown-and-white calf named Millie, short for Millennium, was born full-term Aug. 23, weighing 62 pounds. She is the third bovine cloned from adult cells born in the United States, but the first Jersey and the first using standard cell-culturing techniques.

"Cloning procedures are more simple than we first thought," said Lannett Edwards, who studied as a visiting U.S. Department of Agriculture scientist with researchers in Scotland who cloned Dolly in 1996. She led the effort here with her husband and colleague Neal Schrick.

The two other cloned cows born in the United States have been produced by researchers at Texas A&M and the University of Connecticut within the past year.

Using ultrasound technology, the Tennessee researchers collected ovarian cells from a cow named Teresa. Next, Edwards removed the DNA from the egg of another cow, leaving behind egg cytoplasm.

Edwards then joined one of the cultured cells from Teresa to the remaining egg cytoplasm, using a technique called electrofusion. The result was a one-cell cloned embryo that began developing with nuclear DNA entirely from Teresa.

Ninety-five embryos were cultured in the laboratory, allowed to mature for seven days, then transferred to 17 surrogate black Angus beef cows. Millie was among nine pregnancies that resulted and was born after 278 days. A normal pregnancy for Jerseys is 280 days.

The researchers said this was achieved without patented techniques to slow the development of the donor egg cells - a so-called quiet state used in cloning two other cows in the United States and Dolly the sheep.

"It is significant just to see another lab produce another clone," said Jerry Yang, director of the Transgenic Animal Facility at the University of Connecticut, which cloned a cow using frozen ear cells of a prize Japanese bull.

Cloning cattle reverses ageing

Six cows cloned in the US show signs of being biologically younger than their actual age, scientists announced on Thursday.

April 27, 2000 - BBC

The fact that the process of cloning appears to reverse ageing is a major surprise as Dolly, the cloned sheep, appears biologically older than her age.

The ability to produce young cells of any type may prove lifesaving for a host of age-related disorders.

Scientists remain unsure why this has happened or whether a longer lifespan will result. But they believe the finding will have a profound impact on the use of cloning for medical purposes.

They hope that in the future cloning will enable a patient's own tissue to be used to grow compatible transplant tissue which would also be youthful. Such tissue could be used to treat diseases of ageing such as Alzheimer's, arthritis and heart disease.

Turning back the clock

The cloning process used by the US and Canadian team seemed to have literally turned back the ageing clock in the cells of the six heifers.

One of the researchers, Robert Lanza of Advanced Cell Technology, Massachusetts, told the BBC: "There is a very real possibility that, if this cellular phenomenon transfers into an entire organism, you would end up with a patient or an animal that had a longer life span."

Persephone is nearly one but has the cells of a newborn

If the same increase was seen in whole organisms as was seen in the cells, then, said Dr Lanza: "For a human who might naturally be able to live for 120 years, they could very well live to 200."

However, the research breakthrough will lead to renewed questions over the ethics and safety of cloning animals or humans, as well as the ethics of extending the lifespan of people.

Dr Lanza said: "We think it would be premature and not safe to apply our work to humans at this point and not ethical to use it for any other purpose than therapeutic reasons, i.e. to alleviate suffering from disease."

Worn out

Scientists calculate the biological age of cells by looking at telomeres. These are little caps on the ends of the chromosomes that carry the genetic blueprint inside cells.

Each time a cell divides, the telomeres become a little worn. When they are frayed beyond repair, the cell dies.

When Dolly was born in 1997, her cells appeared to be the same age as the cells of the 6-year-old ewe from which she was cloned.

However, the six heifers, cloned by taking cells from a 45-day-old foetus and placing them in an egg, have exceptionally young telomeres.

Time machine

"The egg cells acts like a little time machine and can take it back, as far as we can tell, to the beginning of life," said Dr Michael West, president of ACT.

He believes the medical implications are far-reaching: "It's the first day in a new era in treating age-related disease. We could take one cell from a patient, make hundreds or thousands of young cells and give them back a young immune system or give them back young cartilage in their knees."

However, producing those cells will almost certainly involve creating cloned human embryos. These would not be allowed to grow into babies but there remains strong opposition from some groups.

The British anti-abortion charity Life said it was worried about some of the implications of the research.

National chairman Jack Scarisbrick said: "If this research hastens the drive towards cloning using embryonic cells, which inevitably causes the death of a human being, then we would deplore it.

"We are totally opposed to cloning of human beings for any purpose whatsoever."

Donor cells

Research is continuing to pin down why cloning bequeathed the US cows younger cells, whereas Dolly was left with older cells.

One factor could be the stage reached by the cell used for cloning. The cells used to clone the cows were still dividing, though near the end of their life cycle. Dolly's creators at the Roslin Institute in Edinburgh, UK, used cells that had been starved and sent into a resting state.

Dolly was also produced from a mammary cell whereas connective tissue cells called fibroblasts were used to produce the cows.

Dr Lanza said: "Previous studies have indicated that there may be variation in how different cell types repair telomeres, which could make the choice of donor cell significant."