Cloned Sheep Dolly Died after Six Years In Brief • Dolly’s premature death is a solemn reminder that cloning is a complex process, still not yet fully understood by cloning researchers. • Scientists should investigate subtleties and monitor cloned animals’ lives until death, so as to properly understand the scope and consequences of any inherent problems. • Other cloned animals after Dolly include: Cumulina the cloned mouse (named for the “cumulus cell” from which she was made), followed by cloned cows, goats, pigs, rabbits, and one small kitten called Carbon Copy.
The world of cloning has been dealt a major setback (2) Mutations of gene and protein structure and with the recent announcement of Dolly’s death. The function, resulting in abnormal embryo growth. world-famous sheep cloned was put to sleep after a (3) Cloned and in vitro embryos have different needs. veterinary examination confirmed that she was suffering from a progressive lung infection. (4) Unnatural origin of a clone’s genetic material. In 1996, Dolly first made the headlines by being In Dolly’s case, one of the biggest fears was that the world’s first successful cloned mammal. Scientists she was cloned from the breast cell of a six-year-old from the Roslin Institute in Scotland had created Dolly adult ewe, and thus might have been born prematurely from a seemingly simple two-step procedure: (1) old. In 1999, scientists discovered that some of the cells Penetrate into the egg, remove its genetic material, then in her body had started to show signs of aging; and in replace it with DNA from a body cell, such as a skin or 2002, Dolly’s creators found that she had developed mammary cell. (2) With electrical or chemical triggers, arthritis at the relatively early age of five and a half years. stimulate the egg to start dividing like a normal fertilized (A sheep of her breed usually lives up to 12 years.) egg. This cloning experiment once hailed as a In other related news, Australia’s first cloned sheep revolutionary breakthrough in science is now serving has also mysteriously died despite being in apparent as a solemn reminder to researchers of the dangers of good health. An autopsy failed to find any reason for its “playing God”. death. Cloning is still very much a field in its teething The merino ewe Matilda was created by technology stages — with far more recorded failures than successes. similar to that which produced Dolly. However, Mr Rob After all, it did take 277 failed attempts before Dolly Lewis (executive director of the South Australian was created. Research and Development Institute), did not think that Matilda’s demise was caused by premature aging as in In animal experiments, only a mere one percent of Dolly’s case. cloned embryos survive to birth. Of those that survive, most suffer from health problems such as heart, lung Researchers say it will take years, probably even and weight abnormalities. decades before science comprehends the intricacies of the highly complex process of cloning. Before then, There are many theories as to why clones fail: mankind would be foolish to embark on any attempts (1) Initial physical damage to the nucleus or the cell’s to clone humans without running the risk of introducing other viscous organelles, which contain all the subtle genetic errors that could create deformed and essential chemicals for normal development. diseased children.
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