[atlasair]

There have been twin studies that show genetics plays a huge part in schizophrenia and ADHD.

It's well known that trauma plays a part, but it is obviously not the whole story.

Twin studies: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4623659/ https://www.ncbi.nlm.nih.gov/pubmed/21336711