Which cells distinguish the human brain from that of other primates?


Three geneticists have taken it upon themselves to investigate why the human brain is so different from a primate.
It took many years of slow, concentrated research. It wasn't until 13 years later that the geneticists had fully mapped human DNA. Five years later, the chimpanzee's DNA. . To their amazement, it turned out that the genes of humans and a chimp are 99 percent identical.
The question immediately arose: what distinguishes our brain from that of a chimpanzee and other animal species.
Because even though the DNA differs so little from the DNA, it clearly has a completely different behavior than that of humans.
Comment with a minimum of 20 words.