Friday, July 16, 2010

Strange genetic experiments


Nazi scientist created a twin-town

The steely hearted "Angel of Death", Josef Mengele, whose mission was to create a master race fit for the Third Reich, was the resident medic at Auschwitz from May 1943 until his flight in the face of the Red Army advance in January 1945. His task was to carry out experiments to discover by what method of genetic quirk twins were produced – and then to artificially increase the Aryan birthrate for his master, Adolf Hitler.

Historians claim Mengele's notorious experiments may have borne fruit. For years scientists have failed to discover why as many as one in five pregnancies in a small Brazilian town have resulted in twins – most of them blond haired and blue eyed. But residents of Candido Godoi now claim that Mengele made repeated visits there in the early 1960s, posing at first as a vet but then offering medical treatment to the women of the town. Shuttling between Argentina, Paraguay and Brazil, he managed to evade justice before his death in 1979, but his dreams of a Nazi master race appeared unfulfilled.


Scientists are developing spider-goats to produce sought materials

What do you get when you cross a spider with a goat? It sounds like it should be the start of a joke, but the spider goat project reflects just one of many disturbing genetic hybridisation projects. Genetic scientists have incorporated selected spider DNA into goat embryos to engineer a hybrid spider goat – and here's why…. Spiders can produce an amazing substance, highly desirable, more valuable than gold – that substance is spilder silk.

Nexia Biotechnologies in Quebec along with scientists at the U.S. Army's Soldier Biological Chemical Command (SBCCOM) in Natick, Mass, have taken the specialized silk producing gene from a spider and inserted it into a goat embryo. The result is a goat……that looks like a goat, acts like a goat, but produces milk which contains proteins which, when treated, produce a very close imitation of the valuable spider silk. A single goat only produces small amounts of the desired material, so an extremely large herd is required to acquire useful quantities.


Scientists create new life from a mouse that has been frozen for 16 years

Scientists have created clones of a mouse that had been dead and frozen for 16 years. It is the first time they have been able to clone a frozen animal. The Japanese researchers say their work will benefit mankind - and could be used to bring back extinct animals such as the woolly mammoth or sabre tooth tiger. Critics say it brings the world closer to the day when people try to clone long- dead relatives stored in cryopreservation clinics. It could even lead to a macabre new industry - in which people leave behind 'relics' of their bodies in freezers in the hope that they could one day be cloned. The latest experiment comes more than 11 years after British scientists stunned the world with Dolly the cloned sheep. Although scientists have since cloned a host of different animals, using genetic material from single cells, they have always used living cells.


Scientist are creating a modified mosquito to fight other mosqiutos

A genetically modified (GM) strain of malaria-resistant mosquito has been created that is better able to survive than disease-carrying insects.

It gives new impetus to one strategy for controlling the disease: introduce a transgenic mosquito carrying a gene that confers resistance to the malaria parasite into wild populations in the hope that they will take over. These mosquitoes had another gene inserted into them to make their eyes fluoresce, to distinguish them from the ordinary strain. The insect carries a gene that prevents infection by the malaria parasite. The researchers caution that their studies are still at an early stage, and that it could be 10 years or more before engineered insects are released into the environment. The approach exploits the fact that the health of infected mosquitoes is itself compromised by the parasite they spread. Insects that cannot be invaded by the parasite are therefore likely to be fitter and out-compete their disease-carrying counterparts.


Scientists demonstrate that girls are genetically predisposed to pink

We all know that women like pink and men prefer blue, but we have never really known why. Now it emerges that parents who dress their boys in blue and girls in pink may not just be following tradition but some deep-seated evolutionary instinct. Researchers have found that there could be sound historical reasons why women have developed a heightened appreciation of reds and pinks, while men are drawn to blue.

The scientists from the University of Newcastle upon Tyne, who were led by Dr Hurlbert and Yazhu Ling, averaged people's overall preferences. The male favourite was a pale blue while the female favourite was a lilac shade of pink. The participants in the study were Chinese and British. The Chinese students showed a marked preference for red. As red symbolises luck and happiness in China, this indicates that cultural norms are also involved. In the study, which is published in the journal Current Biology, the scientists showed pairs of colours to 208 volunteers aged between 20 and 26, who had to select which they preferred by clicking with a computer mouse. Both groups showed similar sex-related preferences, with women liking blues and pinks while men liked mainly blues.

There is already evidence that human's ability to see in colour is likely to have evolved because of the usefulness of being able to distinguish red fruits from green backgrounds. The female role as gatherers while males hunted could have favoured a particular preference for reds and pinks, the scientists said. Dr Ling said the team was now seeking to investigate further the extent to which these preferences are innate. Her own favourite colour? "A very paleish pink," she said.


Scientists are trying to grow human eyeballs

A genetic switch that gives tadpoles three eyes could allow stem-cell scientists to eventually grow human eyeballs or at least create replacement parts needed for repair jobs. If scientists could grow eyeballs from stem cells in the lab, the process would be a boon to individuals with damage to cells within the eye, including retinal disorders.

Scientists had already established the amphibian genes that initiate and direct eye development, which they refer to as Eye Field Transcription Factors (EFTFs). How these genes get activated in the right location at a certain time during development had been cloaked in mystery. But in 2007, a new study suggested a nitrogen-bearing molecule sets off a series of steps that result in eye formation in frogs. When researchers injected a specific enzyme into frog embryos, the resulting tadpoles showed an extra eye. The mechanism probably also applies to humans and other animals with eyes. Dale and University of Warwick developmental biologist Elizabeth Jones, along with colleagues, discovered the eye-switch while investigating how "ectoenzyme" molecules located on the external surface of cells contributed to the development of locomotion in the African clawed frog (Xenopus laevis). The biologists injected the molecules into frog embryos that comprised just eight cells.

One of the ectoenzymes triggered wonky eye development. When added to cells that would eventually form the head, the resulting tadpole sported three eyes instead of two. An even stranger sight resulted when they injected the ectoenzyme into other developing body cells. The molecule caused an additional "ectopic" eye, leading to tadpoles with a spare peeper growing out of the side, abdomen or even along the tail.


Dutch scientists create genetically engineered cows to produce fortified milk

A Dutch biotechnology company called Pharming has genetically engineered cows, outfitting females with a human gene that causes them to express high levels of the protein human lactoferrin in their milk. According to Pharming's website, the protein —which is naturally present in human tears, lung secretions, milk and other bodily fluids—fights against the bacteria that causes eye and lung infections, plays a key role in the immune system of infants and adults and improves intestinal microbial balance, promoting the health of the gastro-intestinal tract. "Since the protein has the ability to bind iron, is a natural anti-bacterial, anti-fungal and anti-viral, is an antioxidant and also has immunomodulatory properties, large groups of people might benefit from orally administered lactoferrin," the company literature reads. Scientists have tested the toxicity of the protein—isolated from the cows' milk—on rats. They found that—even at the high level of 2,000 mg recombinant human lactoferrin per kg body weight—orally consumed human lactoferrin has no adverse effects to complement all the supposed benefits already mentioned.


Scientists are trying to create fastest trees

A tree that can reach 90 feet in six years and be grown as a row crop on fallow farmland could represent a major replacement for fossil fuels. Purdue University researchers are using genetic tools in an effort to design trees that readily and inexpensively can yield the substances needed to produce alternative transportation fuel. The scientists are focused on a compound in cell walls called lignin that contributes to plants' structural strength, but which hinders extraction of cellulose. Cellulose is the sugar-containing component needed to make the alternative fuel ethanol. With funding from the Department of Energy, Clint Chapple and Rick Meilan are using genetic tools to find ways to convert trees into ethanol as a replacement for fossil fuels.

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