Population geneticists have produced the first high-quality genome of a Neanderthal, allowing comparison with the genomes of modern humans and Denisovans. The analysis shows a long history of interbreeding among these early humans and a fourth, previously unknown group. The Neanderthal, from Denisova cave, also shows evidence of inbreeding. About 87 genes in modern humans were found to be significantly different from related genes in Neanderthals and Denisovans.