The evidence that humans are most closely related to the African apes is overwhelming. On the basis of all the evidence, the closest relative of the human proves to be the chimp. The closest relative of the chimp is the human. Not orangs, but people. Chimps and humans are nearer kin than are chimps and gorillas or any other kinds of ape not of the same species.
Gorillas are the next closest relatives, both to chimps and humans.
The more remote the kinship when we go to monkeys or lemurs or, say, tree shrews the less the similarity in sequence. By these standards, humans and chimps are about as closely related as horses and donkeys, and are closer relatives than mice and rats, or turkeys and chickens, or camels and llamas. Maybe the chimp's cytochrome c and hemoglobin are almost the same as mine. But the chimp isn't nearly as smart as I am, as well-organized, as hardworking, as loving, as moral, as devout. Maybe when the genes for these traits are discovered, bigger differences will be found.