What happens if human cells contribute to the growth of a chimera brain? Should the chimera be considered a person

No. it should be considered its kin (Kind) as a chimera

Explanation:

The reason why is because lets say we have a human. Totally normal and fine, but then there cell's get all jittery and there mind gets transformed. So then  they start acting like a wolf, because the cells contributed to the growth of a wolf brain. They'd be considered a Were-Wolf then would be put in asylum to be studided and to keep humanity safe. So yes by law they are still a person. But in consideration, No they are not to be considered a person.

chromosomes carry the genetic information for organisms. also, chromatin is the thread like dna which is located in the nucleus of an organism.