Not exactly, Homo erectus and Neanderthal's both ate meat. The consumption of meat by Homo erectus was associated with a reduction in the size of the gut area due to consistently incorporating animal foods into their diet. Neanderthals were known to be skilled hunters as well. The biggest difference between us and our more recent ancestors is the truncation of a GTPase gene in our DNA, which led to the ability to have neurons grow on top of one another. Previously, neuron growth would be stopped when a neuron came into contact with another. So that's without question the biggest genetic feature that sets us apart.