Dr. Tim Karr from the Department of Biology and Biochemistry at the University of Bath

Using molecular techniques, the researchers found that the Drosophila paternal effect gene they were characterising was only present in the melanogaster sub-group of fruit fly, but its progenitor, or ancestor, was present in all of the different sub-groups.

Using statistical information about the rate at which genes evolve, the researchers worked out that the gene was only about 1-2 million years old, and much younger than the majority of the genes in the remainder of the fruit fly genome.

This finding, that an essential gene has a relatively recent origin, overturns the conventional notion that genes with vital functions must have been created a long time ago, but raises important questions about why and how this particular gene evolved.

“This discovery really changes our concept of how new gene function can evolve, which is a major issue for evolutionary biology,” said Dr Tim Karr from the University of Bath, who made the discovery with colleagues in the Centre de Genetique Moleculaire et Cellulaire in France and the University of Chicago.

“It is remarkable to think that through a range of random, naturally-occurring genetic changes over a few million years, a new essential gene has evolved. Obviously other species of fruit fly don't need this gene but they may have other genes that serve a similar function. At first the gene may have conveyed some as yet unknown benefit that eventually became essential during the course of evolution. It could even have been involved in the early processes leading to speciation of this group of fruit flies,” said Dr Karr.

Dr Steve Dorus from the University of Chicago, who collaborated on the project, will be joining the Karr laboratory at the University of Bath this month to continue studies on this, and other paternal genes.

“The fact that this essential, newly-evolved gene is a male factor that is required for successful embryo development after fertilisation makes it all the more interesting. Paternal effect genes have only recently become the subject of scientific investigation, and the genetic characterisation of this gene will help further investigations in this area,” said Dr Karr.

“I would be very surprised if there were not more examples of paternal effect genes spread throughout the animal kingdom. Because we know so much about the relatively simple genetic makeup of the fruit fly, it is yet another example of where Drosophila can help us understand important genetic processes throughout the animal kingdom, including humans.”

The research was funded by the Royal Society.

Re: Theory on evolution of essential genes is overturned by new finding Sarah90    August 4th, 2005 - 5:55 AM I guess this is pretty ordinary by now...dawg cloned.�  �  �    World’s first canine clone is revealed 18:00 03 August 2005 NewScientist.com news service Rowan Hooper A family portrait, with clone Snuppy (centre), his clone ‘father’ and surrogate labrador mother (Image: Seoul National University)Related Articles Cloned human embryos deliver tailored stem cells 19 May 2005 First clone of champion racehorse revealed 14 April 2005 Cloners set their sights on rare cats 08 January 2005 Search New Scientist Contact us Web Links Seoul National University (in Korean) Gerald Schatten, University of Pittsburgh School of Medicine Nature   Cloning dogs has been harder to do than other mammals cloned so far (Image: Seoul National University)The world’s first cloned dog has been revealed by researchers. South Korea’s “king of cloning”, Woo Suk Hwang has successfully cloned an Afghan hound. The breakthrough is bound to lead to excitement among dog lovers who long to clone their dead pets, but Gerald Schatten at the University of Pittsburgh School of Medicine, US, has stern words. “We are not in the business of cloning pets,” he says. “We perform nuclear transfer for medical research.” Producing “Snuppy” – or Seoul National University puppy – was not easy. Hwang’s team put together 1095 eggs containing the DNA of a three-year-old adult male Afghan, and transferred them into 123 surrogate mothers. Just three pregnancies resulted: one miscarried, and two others went to term. One of the clones died from pneumonia at 22 days old. “Professor Hwang and his colleagues are to be congratulated on another great success,” says Ian Wilmut, creator of Dolly the sheep, at the University of Edinburgh, UK. Happy families The team used somatic cell nuclear transfer, the same technique used to create Dolly. To clone Snuppy, the researchers implanted nuclei from his father’s ear cells into eggs from female dogs, having removed the eggs’ nuclei. After being zapped with a small electric shock to start development, the embryos were implanted into the uterus of a surrogate mother – in Snuppy’s case, a labrador. The team used DNA fingerprinting to confirm that Snuppy was genetically identical to his “father”. To see the happy clone family frolicking, click here for a short video (15 MB, avi format, requires RealPlayer or Quicktime). Research applications Successful nuclear transfer in dogs has been elusive until now because it is difficult to get egg cells to mature in the lab. Hwang got around the problem by using naturally ovulated egg cells – those which have naturally been released from the ovaries into the fallopian tubes. Snuppy is the latest mammal to be cloned after sheep, mice, cats, rats, cows, goats, pigs, horses, rabbits and a mule. There are many research applications for cloning in dogs, says Katrin Hinrichs, of the College of Veterinary Medicine at Texas A&M University, US, who was the first to clone a horse in the US. “There are human diseases for which we have dog models,” she says. “It would be of great benefit to have multiple genetically identical animals to study the pathogenesis and treatment of these diseases.” Inherited diseases, for example are a serious problem in purebred dogs. Many, such as malformed hip joints, are influenced by both genetic and environmental factors, and having clones will enable scientists to tease apart these factors. Dogs in a dish Schatten, who was part of Hwang’s team, says that the cloning of dogs is a step towards the cloning of canine stem cells. Stem cells can currently only be cloned in mice and human cells. “Once stem cells can be established it may be possible to learn about the genetic basis of traits by studying cells in a dish rather than in the dogs themselves,” he says. But despite Schatten’s warning, many people are likely to immediately look to the possibility of cloning beloved pets. “I am sure that some people will think that it is worth spending money to have a puppy with a specific genotype,” says Hinrichs. Why did they choose an Afghan to clone? “Having a distinctive dog means that if we’d [ended up with] a dachshund we’d know that something funny had happened,” says Schatten. Journal reference: Nature (vol 436, p 641)

Re: Theory on evolution of essential genes is overturned by new finding yale    August 7th, 2005 - 1:07 PM Be prepared for glow-in-the-dark pets. It is common in biological research to insert luminous organism genes into test subjects. The glow is a useful tool to track gene expression and embryonic development. It is inevitable that various plants and animals will be bred for novelty pets with glow-in-the-dark features. I suspect that even glow-in-the-dark foods will eventually be marketed. yale

Re: Theory on evolution of essential genes is overturned by new finding yale    August 7th, 2005 - 1:09 PM GM fish glows in the bowl   By Dr David Whitehouse BBC News Online science editor  A Taiwanese company has created a genetically modified (GM) ornamental fish that glows in the dark.   But will they catch on? The Taikong Corporation took DNA from a jellyfish and inserted it into a zebra fish to make it shine a yellow-green colour. GM animals are frequently used in labs and flocks of GM sheep make valuable proteins in their milk, but the "Night Pearl" zebra fish is the first gene-altered pet to go on sale to the public. For some, the animal will be a fascinating novelty; for others, it will raise fears of a trend for bio-engineered "Frankenstein pets". The Taikong Corporation reports strong interest in its creation from the UK, where the aquatic industry is worth millions. Safe and sterile Taikong insists the GM fish, designated TK-1, is safe, sterile and that its additional fluorescent gene is harmless. The fish was unveiled in 2001, but it took another year and a half to develop a technique to render the animal sterile. It cannot cross-breed with natural fish. TK-1 was developed using the work of HJ Tsai of the National Taiwan University. Initially, Taikong plans to sell 30,000 glowing fish at US $17 each and then increase production to more than 100,000 in three months. But not everyone is enthusiastic. Aquatic industry specialists are worried TK-1 may be the first of many GM pet fish destined for Britain. In particular, some tropical fish are being bio-engineered to tolerate cold and could colonise UK waters if they escaped, disturbing the present ecosystem. According to Derek Lambert, of Today's Fishkeeper magazine, GM piranhas could survive in our waterways and pose a major problem. He is urging traders to boycott the TK-1. Keith Davenport, of the Aquatic Ornamental Trade Association (AOTA), commented that interfering with the genome was unnecessary and said people did not want animals to become fashion accessories.

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