Basically it's what this person said.

Also remember, even IF DNA in brain cells are indeed dynamic, there is no mechanism that allows this DNA to be reflected in your reproductive cells. So long as it is not in your sperms and ovums, it will not be passed.

You can change the DNA of target cells, but you can't change the DNA of a person - to do that, you would have to change millions of individual cells who each have copies of DNA.