[escepticos] Clonación humana en Corea

["Victor R. Ruiz" <rvr@...>]

  Hola:

  Con tanto Tomahawk volando sobre nuestras cabezas ha pasado casi
desapercibida la noticia de que científicos coreanos han logrado clonar un
embrión humano. Aquí va la respuesta de los papás de Dolly:

. . . .

Dolly's Makers Doubt Koreans Cloned Human Embryo

   By Patricia Reaney

   LONDON (Reuters) - Scientists who created Dolly the sheep, the world's
   first cloned animal, said Wednesday they did not believe South Korean
   researchers had cloned a human embryo.
   ``We don't believe they have provided any evidence that they have
   achieved what they claimed to have achieved,'' Dr. Harry Griffin, of
   the Roslin Institute in Edinburgh, said in a telephone interview.

   ``The story is grossly overblown.''

   Lee Bo-yon and researchers at Kyunghee University Hospital in Seoul
   said Wednesday that they had cultivated a human embryo using an
   unfertilized egg and a somatic cell, those that make up most of the
   body, donated by a 30-year-old woman.

   The Korean researchers said they aborted the experiment after the
   human embryo divided into four cells.

   ``If implanted into a uterine wall of a carrier, we can assume that a
   human child would be formed and that it would have the same gene
   characteristics as that of the donor,'' Lee said.

   Somatic cell transfer is the same technique the Roslin scientists used
   to create Dolly in 1996. Griffin said it was technically possible to
   clone a human embryo ``but this group hasn't done it.''
   Humans start off as a single cell which then divides repeatedly, but
   it is only after three cell divisions that the nucleus takes over
   control of the development of the embryo.

   ``The Korean group stopped the experiment when they saw four cells
   being produced so there is no evidence that the somatic cell they
   transferred was reprogrammed,'' Griffin said.

   He added that he and his colleagues were also puzzled about why Lee
   went ahead with the experiment now. They said there was no indication
   that the Korean work was part of a large research program and the
   South Korean government was considering legislation to control
   research on human cloning.

   Griffin denied that Roslin scientists had already cloned a human
   embryo.

   ``There is no substance to the suggestion by Dr Lee Bo-yon that the
   Roslin Institute has already cloned a human embryo. We have done no
   research on cloning with human cells. Such research is currently
   illegal in the UK,'' Griffin said in a statement.

   Last week a panel of scientists advised Britain to allow the cloning
   of human embryos to create tissue and organs, but they supported the
   government's ban on human reproductive cloning.

   If the recommendation is approved by the government, scientists will
   have to apply for a license to do the research.

   ``In the UK an embryo would only be allowed to grow for 14 days. At
   this stage it would be a small ball of cells barely visible to the
   naked eye. Implantation of the embryo in the uterus of a woman would
   not be allowed and neither is it necessary for recovery of human
   embryonic stem cells,'' Griffin said.

   Scientists hope that stem cells, which have the potential to be
   converted to specific cell types, could be used to treat patients
   suffering from ailments such as Parkinson's disease, stroke or heart
   attack. Griffin said it was extremely unlikely that whole organs could
   ever be grown in the lab.

   Dolly was produced by taking the nucleus out of a cell from the
   mammary gland of an adult animal and fusing it, using an electrical
   current, into another sheep egg cell from which the nucleus had been
   transferred.

   Since her creation scientists at the University of Hawaii have cloned
   50 mice from adult cells and Japanese researchers have produced up to
   eight calves from a single adult cow.

. . . .

  Más información en:

http://dailynews.yahoo.com/headlines/ts/story.html?s=v/nm/19981216/ts/cloning_2.html
http://dailynews.yahoo.com/headlines/ts/story.html?s=v/nm/19981216/ts/cloning_3.html

  Saludines,

Víctor R. Ruiz
rvr en idecnet.com