European scientists have been the big winners in this year's Nobel Prize announcements so far, scooping prizes for medicine and physics for their scientific breakthroughs. One Italian-born and two British-born scientists were awarded the Nobel Prize for medicine for their groundbreaking discoveries in gene technology. Two of the three do now have US nationality. Mario Capecchi, Oliver Smithies and Briton Martin Evans developed a technique known as gene targeting in mice that enabled them to replicate human diseases in mice by introducing genetic changes into the animal's stem cells. According to the Nobel Committee, this has led to many new insights into conditions such as cancer and heart disease. In its citation, the Nobel Committee praised the technique as 'an immensely powerful technology', which is now being used in virtually all areas of biomedical research. 'Gene targeting in mice has pervaded all fields of biomedicine. Its impact on the understanding of gene function and its benefits to mankind will continue to increase over many years to come,' it said. The technique is commonly described as gene 'knockout' as it enables scientists to silence specific genes, and monitor the effect, so that gene-by-gene they are able to build a picture of embryonic development, adult physiology, ageing and disease. Until now, more than 10,000 mice genes have been inactivated, with more predicted to follow soon. As a result, more than 500 different mouse models of human disorders have been developed, including cardiovascular and neuro-degenerative diseases, diabetes and cancer. In the physics category, the Frenchman Albert Fert and Peter Grunberg from Germany were jointly awarded the prize for their discovery of the phenomenon of giant magnetoresistance (GMR), in which weak magnetic changes give rise to big differences in electrical resistance. The discovery in 1988 made possible the development of sensitive reading tools able to acquire the data on hard drives found in computers, iPods and many other digital devices. It has also made possible the radical miniaturisation of hard disks in recent years. GMR involves structures consisting of very thin layers of different magnetic materials. For this reason it can also be considered 'one of the first real applications of the promising field of nanotechnology', the Royal Swedish Academy of Sciences said in a statement. 'Applications of this phenomenon have revolutionised techniques for retrieving data from hard disks,' the prize citation said. 'The discovery also plays a major role in various magnetic sensors, as well as for the development of a new generation of electronics.'