We could soon find out how the Neanderthal DNA many of us carry actually affects us. It turns out that stem cells, which have been hyped as a way to treat incurable diseases, can also be used to examine what Neanderthal genes do.

Since 2010 evidence has been growing that many living people carry tiny amounts of Neanderthal DNA in their cells . It’s been suggested that this Neanderthal DNA has all sorts of effects, from our immune systems to skin colour . …