Scientists have succeeded in sequencing the genome of gorillas and the results show humans are more closely related to the threatened primates than previously thought:

(SidneyHer) — Scientists … also found that 15 per cent of the gorilla’s genetic code is closer between humans and gorillas than it is between humans and chimpanzees, our closest animal relative. The genomes of all three species are, in any case, highly similar: humans and chimpanzees share more than 98 per cent of their genes, while humans and gorillas share more than 96 per cent.

Some of the familial continuity between all three closely related clades might be best explained by interbreeding for eons after the three began to split. It is believed the human-chimp line diverged from the one that led to modern gorillas about 10 million years ago, and the chimp vs human ancestors split happened about 6 million years ago.