Researchers at San Raffaele Scientific Institute in Milan and Lund University have independently worked out how to turn skin cells into specialized neurons that make dopamine, which is depleted in the brains of people with Parkinson’s disease.

The studies raise the possibility of improving mobility in people with Parkinson’s by restoring dopamine production to normal. At present, most patients take a drug called L-dopa to readjust levels, but with varying levels of success.

The San Raffaele team reprogrammed mouse skin cells using three transcription factors — proteins previously linked with the development of the neurons. The factors transformed skin cells taken from human embryos, healthy adults, and people with Parkinson’s.

The Lund University team converted human skin cells from embryos into neurons, then into specialized ones that make dopamine. Altogether, they used five transcription factors, including Mash1 and Lmx1a.