Bleating cousins

-- IT TOOK a simple laboratory dish to create one of the most awesome break-
throughs in science - hundreds of
genetically identical sheep. The feat was
recently performed by Ian Wilmut,
Keith Campbell and their colleagues at
the Roslin Institute in Edinburgh. The
process itself does not seem too complex - taking an embryo from a pregnant sheep and allowing it to multiply in
culture dishes; removing eggs from
female sheep and then stripping them of
their genetic material; and finally, fusing
the cultured cells with the eggs in test
tubes to create new embryos with
similar genetic material. These were
then-implanted in a surrogate mother
sheep. And the result: the first two
genetically alike sheep, christened
Megan and Morag.

What the future could hold for these
experiments is tremendous. In theory,
the technique would hold good to create
identical humans. Imagine an array of
budding Einsteins or Kasparovs dotting
the earth. "It's very impressive," said
David White, a lecturer at the
Cambridge University and a founder of
Imutran, a biotech company producing
genetically engineered pigs, of the
Scottish achievement.

While cloning has been conducted
in laboratory animals like rats and rabbits with partial success, this is the first
time that it is being carried out in a larger
animal. "The production of cloned off-
springs in farm animal species could
provide enormous benefits in research,
agriculture, and biotechnology,"
according to Campbell and his colleagues. Cloning of sheep itself offers
immense possibilities - sheep with better wool, stronger hooves and greater
resistance to diseases could be produced
by adding the right genes to the cultured
cells. Further, the new"process fastens
the introduction of a new genetic trait in
animals, while earlier it used to take
years of cross-breeding to develop
the same.

A word of caution, however. A
sudden outbreak of a disease, to which
resistance has pot been developed,
could catch the identical breeds
unawares, leading to a mass extinction.

This is what had occurred in Chile
sometime ago, when asexually
produced blackberries were ravaged by
a rust fungus which did not affect the
sexually produced variety. Ultimately,
diversity in nature is a fat more pleasing
sight than unending streams of similar
animal and plant species.