Coleman and other scientists have long wondered how sick and healthy cells can be interspersed throughout the brains of the 4 million people in the United States who have the disease. Understanding why some brain cells die while others nearby thrive may be the key to understanding the disease itself, Coleman says. The technology the team developed last year allows scientists to study brain cells in unprecedented detail by simultaneously measuring the activity of several genes in a single cell, to see which genes are turned on and which are dormant. They've looked at a few dozen genes thus far, and they plan soon to look at the activity of 20,000 genes from a single cell simultaneously. Early studies indicate that some of the same genes involved in cancer may also play a role in Alzheimer's disease.
Cancer cells grow and divide uncontrollably, eventually pushing aside healthy cells.
Coleman's team of 12 students and professors has found that the activity of some of the same genes involved in cancer differs dramatically between healthy and sick cells in Alzheimer's disease. In one class, says Coleman, the teacher handed him a piece of brain from a rat and asked Coleman to analyze the genes within it. Taking on new questions has been a consistent theme throughout Coleman's career. He had spent years studying the way the healthy brain works when he and a student decided one day to take a detailed look at brain tissue damaged by Alzheimer's disease. The 1979 work was among the first to show precisely what happens in the brains of patients who have the disease.