Researchers at State University of New York-Buffalo have managed to grow human brain cells afflicted with Parkinson's disease in vitro, reports Popular Science's Rebecca Boyle. The cells, derived from the skin cells of Parkinson's patients, may help researchers track how mutations in the parkin gene can lead to the disease, Boyle says. "This is a major breakthrough because it will allow researchers to study brain cells affected by Parkinson's in real time," she adds. "Animals that do not have this gene cannot readily develop Parkinson's-like symptoms, so researchers must use human neurons, but it's generally difficult if not impossible to get live human brain cells to study." In their study, published in Nature Communications, the researchers say they took skin cells from two healthy patients and two patients with the parkin mutation, induced them into becoming pluripotent stem cells, and then differentiated the stem cells into dopaminergic neurons — the loss of which causes Parkinson's symptoms. "The Parkin gene mutation was present in the donors' DNA, so the lab-created brain cells had the same traits that the patients' real brain cells would have," Boyle says. "This allowed the researchers to watch the gene mutation at work." The researchers also found that when they introduced the normal version of parkin into the affected cells, they could reverse the defects caused by the mutation, she adds.