Clone wars
From sheep to cow and deer, and even claims of humans, the cloning controversy rages on. Here are some highlights of the latest in the cloning saga.
Dolly dies
DOLLY the sheep, the first mammal to be cloned from an adult cell, was put down on Feb 14, after developing a progressive lung disease. Dolly’s birth 6½ years ago caused a sensation around the world. But as many sheep live to twice this age, her death will refuel the intense debate over the health and life expectancy of cloned animals. The type of lung disease Dolly developed is most common in older sheep. In January 2002, it was revealed that Dolly had developed arthritis prematurely. She was cloned using a cell taken from a healthy six-year-old sheep, and was born on July 5, 1996 at the Roslin Institute, Edinburgh, Scotland. Dolly was donated to the National Museum of Scotland in Edinburgh, where she was stuffed and put on display.
Virgin birth
ON JUNE 10, the team that cloned Dolly the sheep was granted Britain’s first stem cell research licence allowing the creation of human embryos from unfertilised eggs. This process is called parthenogenesis – Greek for “virgin birth” – and occurs naturally in some reptiles and insects. It allows females to reproduce without males, as their eggs are prompted to develop into embryos without being fertilised by sperm. Ian Wilmut and colleagues at the Roslin Institute, Edinburgh, will artificially stimulate human egg cells to undergo parthenogenesis and then take stem cells from the resulting embryos. Their aim is to develop the technology needed to maintain cell lines of human embryonic stem cells in the laboratory. The one-year research licence was granted by Britain’s Human Fertilisation and Embryology Authority.
Zulu replica
SOUTH African and Danish scientists carried out Africa’s first animal cloning, a calf born in April at a research institute near Johannesburg – a researcher at the Embryo Plus centre announced on May 8. The 32kg calf was named Fut meaning “replica” or “repeat” in Zulu.
Crying foal
THE birth of the world’s first cloned horse was announced on Aug 3. The healthy female foal – named Prometea – was born to her genetically identical surrogate mother on May 28. The breakthrough follows the cloning of a mule earlier this year. Cesare Galli, director of the Laboratory of Reproductive Technology in Cremona, and colleagues created Prometea by fusing the nucleus of a skin cell taken from the mother with an empty egg from another horse. The resulting embryo was returned to the mother’s womb after being cultured in the lab. Galli says cloning horses could help boost good breeds and might even help replicate equine champions.
Dewey a deer
SCIENTISTS at Texas A&M University announced on Dec 22 that they have cloned a white-tailed deer which they named Dewey.
Human claim
CONTROVERSIAL reproductive scientist Panayiotis Zavos on April 3 published a short report and picture of what he claims is “the first human cloned embryo for reproductive purposes”. The single four-day-old embryo, which comprised eight to 10 cells, was revealed in a commentary in Reproductive BioMedicine Online. Zavos said the embryo was created by somatic cell nuclear transfer (SCNT), the same technique used to make the famous cloned sheep Dolly. In SCNT, a cell is fused with an egg stripped of its own genetic material.
Ban deferred
THE UN General Assembly in New York narrowly voted Nov 3 to postpone any ban on human cloning until 2005. The main alternative to the two-year moratorium was a Costa Rican-led blanket ban on both human reproductive and therapeutic cloning, backed by the US government and 43 other countries. Reproductive cloning – creating babies – is regarded by virtually everyone as dangerous and unethical. But opinion is split on therapeutic cloning – the use of cloned embryos to harvest stem cells for medical use. Supporters say the approach offers unrivalled promise for the treatment of many diseases, such as Parkinson’s and diabetes. Opponents, many of whom also oppose abortion, say that the resultant death of the embryo is absolutely unacceptable.
Floating train
A MAGNETICALLY-levitated train set a new world speed record in Japan, reaching 581kph during a manned test run on Dec 2. The Maglev train hovers 10mm above electromagnetic rails which propel the locomotive without the need for an engine. The Maglev is part of a government-financed project to develop faster, quieter trains. Japan’s bullet trains, introduced in the 1960s, are among the world’s fastest.
Malaysian microchip
IT WAS announced on Sept 5 that Malaysia will produce an advanced microchip that can be used for a broad range of applications from detecting forgery to killing cancer cells. The government will jointly produce the next-generation radio frequency identification chip with Japanese company FEC Inc, which designed the chip. Malaysia owns the intellectual property rights to the chip, called MM Chip or Malaysian Microchip. The MM chip, about the size of a dust mote, can be embedded in paper. It is useful for a variety of purposes, such as a replacement for barcode tags in retail goods, for differentiating between genuine and counterfeit currency notes, and for use in passports.
Great ancestors
SCIENTISTS announced on June 13 they have found what they believed to be our oldest immediate ancestors, a finding that sheds fresh light on Homo sapiens’ rise out of Africa and their conquest of the globe. The skulls of two adults and a child, found in the Middle Awash area of central Ethiopia in 1997, have been carbon-dated to between 154,000 and 160,000 years old, around 50,000 years earlier than the previous oldest finds of Homo sapiens.
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