“Is ADHD inherited from the mother or father?”

ADHD can come from either the maternal or the paternal line - or from both. I know many persons with the condition who have relatives with ADHD or other mood disorders on both sides of the family.

The subject of whether emotional patterns, whether it is depression, anxiety, or psychosis, can be inherited is a big subject. The author Jay Joseph has written books about this and concludes that there is no dependable evidence that these difficulties are inherited. There was great hope from the 1950's onward that genetic patterns would be discovered that would make it clear how difficulties were passed on from generation to generation. However, no clear evidence was discovered and promise of "twin studies" also failed to confirm genetic transmission. Therefore, I would answer your question by saying that ADHD is not inherited from either the mother or the father.

It's not always inherited. Maternal smoking is a risk. Genes are not inherited by a single parent.

It could be either or both parents. ADHD is now considered the illness with most heritability surpassing schizophrenia.

Yes, there is a genetic component to ADHD.