LONDON: Scientists looking for the genetic triggers that lead to Alzheimer's have identified five more, doubling the number linked with the mind-wasting disease. If drugs or lifestyle changes could be devised to counter these genetic variations, more than 60 percent of Alzheimer's cases could be prevented, according to the researchers, whose work was published in the journal Nature Genetics Sunday. But those discoveries could be at least 15 years away, they said. Alzheimer's is the most common form of dementia, a fatal brain disease that affects memory, thinking, behavior and the ability to handle daily activities. It is increasingly placing a heavy burden on societies and economies across the world. “We are beginning to piece together the jigsaw and gain new understanding,” said Julie Williams from Cardiff University's centre for neuropsychiatric genetics and genomics, who led the study. “If we were able to remove the detrimental effects of these genes through treatments, we hope we can help reduce the proportion of people developing Alzheimer's in the long-term.” The researchers said the genetic variants they found highlight specific differences in people who get Alzheimer's, including variations in the immune system, the ways the brain handles cholesterol and lipids as well as a process which removes toxic protein from the brain.