The Guardian June 28, 2000


About Cloning:
the history of dynamite must not be repeated

by Raisa Pages

Collecting dead cows' ovaries from a slaughterhouse may seem like something 
from a Frankenstein novel, but this work is part of specialist Milagros 
Cardenas' daily routine at the In-Vitro Fertilisation and Cloning 
Laboratory which is part of the Havana-based Centre for Animal Improvement 
Research (CIMA).

A new life can emerge after death, but an animal doesn't have to be dead in 
order for a living genetic replica to be created. The ability to produce an 
"exact twin" of any animal or plant is one of the scientific 
accomplishments of the 20th century.

It was achieved by cloning technicians, making use of the knowledge 
accumulated over many years about the mysteries of heredity.

Dolly, the famous cloned sheep produced in 1997 by Briton Ian Wilmut after 
267 unsuccessful attempts, opened the way for the science of cloning. It 
became possible to develop a new animal from the somatic or static cells 
contained in skin or muscle tissue and which normally do not have the 
ability to reproduce themselves to form an embryo.

Even though Dolly put the British at the forefront of world advances in 
animal cloning, subsequent work by scientists in France, the United States, 
Germany, Japan, New Zealand and Australia produced a diverse range of 
animals cloned from somatic cells.

"The cloning of animals for its own sake is not the purpose of this 
science", explained Dr Jose Morales, head of CIMA. "By mastering the 
technique, we can modify the hereditary process and thus bring benefits to 
human nutrition and health. 

"The most vital step in the transgenetic process is to obtain individuals 
with the best characteristics from any given group of plants and animals.

"By using these techniques, it's possible to create cows or goats whose 
milk contains the enzyme that is deficient in children who normally have 
intolerance to dairy products. In fact, we know that goats with these 
characteristics have already been produced for children that suffer from 
this problem.

"There is potential benefit for all humankind, in that we can use an animal 
organ in a transplant operation and be sure that it will be compatible with 
the body of its recipient. There would be no need to use donated human 
organs any longer", said Dr Morales.

CIMA forms part of the Cuban scientific team that is working on animal 
cloning and which is headed by Dr Fidel Ovidio Castro, a specialist at the 
Genetic Engineering and Biotechnology Centre, situated to the east of 
Havana.

A French expert's opinion

"To achieve cloning by way of theoretical computer studies of genetics may 
seem easy, but in practice it's very difficult", says Yvan Heyman, second 
in command of the French Institute of Biology and Biotechnology. 

He made his comments during the International Conference on Animal 
Improvement Research, held recently in Havana to celebrate CIMA's 30th 
anniversary.

Attending the conference along with Heyman were French specialists Xavier 
Vignon and Daniel Le Bourhies, who together make up the world's second most 
advanced team, after the British.

Heyman also said that cloning and transgenesis make possible recombinant 
proteins which have human pharmacological uses. He showed photos of cattle 
cloned from the ear tissue of the various bovines breeds such as the 
Holstein.

The birth of cloned bovine embryos, the step prior to transgenesis, 
currently enjoys a success rate of only around 10 percent, due to 
miscarriages by the surrogate cow. The reasons for this are still under 
investigation.

Preparing the way

Cuba has yet to complete the successful birth of a cloned sheep or cow, but 
the way is being prepared for this to happen soon. "We've already reached 
the very important stage of producing embryos from bovine somatic cells, 
which is something that puts us very close to achieving a live birth", Dr 
Morales announced.

"The team calculate that during the coming year we will obtain our first 
cloned cattle."

The UN Food and Agriculture Organisation (FAO) believes that Cuba leads the 
field in the technique of bovine embryo transplant as far as Latin America 
and the Caribbean is concerned. Dr Morales said that the organisation is 
now financing scholarship study courses for the region's students to train 
at CIMA.

He went on to note that a scientific project was under way in Cuba to 
preserve cells from the famous cow Ubre Blanca, which produced more than 
100 litres of milk each day. The intention is to try to produce a clone in 
the future. 

Technician Milagros Cardenas' work of collecting ovaries in slaughterhouses 
is necessary in order to extract the eggs, in which the female sexual cells 
are located. These will be converted into the receptors for the new genetic 
information which comes from the animal selected for cloning.

"The receptors are created by extracting the nucleus from these carrier 
cells, so that the genetic information is erased and then the required 
information is inserted", biologist Marilay Ruiz told Granma 
International during our visit to CIMA.

The most difficult part is the transfer of the genetic information of the 
selected animal. When the cloning is carried out using embryonic cells, the 
process is quicker because they have the capability to reproduce 
themselves.

But the most complex procedure is when they originate from muscle or skin 
tissue which have to be placed in special culture media in order to begin 
reproducing. That's a process that requires a lot of care and observation.

Dolly the sheep, for example, was created by splitting cells from the 
epithelium of the mammary gland of the replicated animal.

International polemic

During his visit to Havana last year, Jacques Diouf, Secretary-General of 
the Food and Agricultural Organisation (FAO), said that the use of cloning 
and transgenetic techniques are vital in order to feed the world's 
population, but that it was important that they are not used in a way which 
violates international ethical principles.

In Cuba, scientists are working to advance the cloning of animals and 
plants with the objective of improving food production. There have already 
been successes in the production of transgenetic freshwater fish, such as 
tilapia, and some vegetables, including the sweet potato.

Internationally, there has been outright rejection of the concept of 
genetically modified foods by some ecology groups, fearful that they could 
be dangerous to humans.

According to an article printed in the London Daily Telegraph and 
reproduced by Prensa Latina, British experts have asked their 
government for permission to clone human embryos for medical purposes. This 
is something that could reopen the debate over the ethics of scientific 
investigations.

British geneticists have explained that the cloning they are requesting 
would allow them to recreate the heart muscle or spinal cord marrow, and 
doesn't represent a threat to society.

A professor of genetics at the University of Utah said that human cloning 
would imply consequences that go beyond science and become a social 
question.

The essence of the subject is that the science of cloning must not follow 
the same path as that of Swede, Alfred Nobel's invention of dynamite, with 
the best of intentions. Nobel died full of remorse about the uses to which 
his discovery was later put.

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Granma International

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