For every person in the world who receives a cornea transplant, there are 69 others who still need one. That leaves about 12.5m people with limited sight because there aren’t enough eye donors. But what if we could grow new corneas in the lab?
In 2006, Nature published a paper describing how stem cells could be used to restore sight in blind mice. This study, and similar subsequent studies, created a lot of excitement about the potential of stem cells to cure blindness in humans. Fast forward 12 years and we still don’t seem to be quite there – one notable human clinical trial in Japan was stopped in 2015 due to a risk of tumour development in a patient’s eye. So are we any closer to using stem cell therapies to treat blindness, or will we always be “ten years away”?
We’ve all had that feeling that somebody is watching us – even if we’re not looking directly at their eyes. Sometimes we even experience a feeling of being watched by someone completely outside our field of vision. But how can we explain this phenomenon without resorting to pseudoscientific explanations like extrasensory perception (or a “sixth sense”)?