Neanderthals had our de novo genes.

Gene duplication provides a profusion of raw material for evolutionary innovation (Lynch and Conery, 2000). While most duplicates rapidly become unrecognizable some, e.g., those that are immediately useful or those that after a period of relaxed selection gain unique roles, are retained and thereby expand a genomes protein-coding repertoire. Ohno (1970) famously remarked that without gene duplication, the creation of metazoans, vertebrates, and mammals from unicellular organisms would have been impossible. Such big leaps in evolution, he argued, required the creation of new gene loci with previously nonexistent functions (Taylor and Raes, 2004). Recently, another source of new genes has been recognized: Though rare, it seems clear that new genes can emerge from formerly non-coding DNA, the de novo protein coding genes (Zhao et al., 2014, and references therein).\n\nIn 2009 Knowles ...