https://phys.org/news/2018-10-human-retinas-grown-dish-vision.html

"Everything we examine looks like a normal developing eye, just growing in a dish," said Robert Johnston, a developmental biologist at Johns Hopkins. "You have a model system that you can manipulate without studying humans directly."

Johnston's lab explores how a cell's fate is determined—or what happens in the womb to turn a developing cell into a specific type of cell, an aspect of human biology that is largely unknown.