For the first time, scientists have grown tiny brains in laboratory dishes that mirror the major pathological features of Parkinson’s disease. The research offers a new way to learn how the disease progresses and study new treatments, investigators at the Genome Institute of Singapore’s Agency for Science, Technology and Research; the National Neuroscience Institute; and Duke-NUS Medical School announced this week.

Prior research on Parkison’s has mostly relied on mice, which do not reproduce all major pathological features seen in patients, noted Professor Ng Huck Hui, senior group leader at GIS and a senior co-author of the study.

“Recreating models of Parkinson’s disease in animal models is hard as these do not show the progressive and selective loss of neurons that produce the neurotransmitter dopamine, a major feature of Parkinson’s disease,” Hui said. “Another limitation is that experimental mouse models of Parkinson’s disease do not develop characteristic clumps of proteins called Lewy bodies, which are often seen in the brain cells of people with Parkinson’s disease.”

The small pea-sized human midbrain-like organoids grow from human stem cells into a bundle of neurons and other cells found in the brain. By manipulating the DNA of the starting stem cells to match genetic risk factors found in patients with Parkinson’s disease, scientists were able to grow organoids with neurons that showed both Lewy bodies and the progressive loss of dopamine-producing neurons.

The team is already using organoids to investigate why and how Lewy bodies form in human brain cells, and screen drugs that can potentially stop disease progression. Full findings of their research was published in Annals of Neurology.