Do You Carry Neanderthal DNA? The Shape of Your Skull May Tell. One of the features that distinguishes modern humans (right) from Neandertals (left) is a globular shape of the braincase. Credit: Philipp Gunz (CC BY-NC-ND 4.0) The shape of your brain may say a lot about the Neanderthal in you. New research has found that modern humans carrying certain genetic fragments from our closest extinct relatives may have more oblong brains and skulls than other people.