Adoptive parents blame my biological family for this

My adoptive mother kept telling me about how I only have illness because my biological family had it meanwhile I wasn’t diagnosed with the same things they have. Anytime I tell her it could be due to the things that happen to me (trauma or my genes) she argues it and says “no not because of me it’s because of your biological mother” (genes). Anytime anything happens she says “you’re born that way” meanwhile there was never a diagnosis until I was older than 10 and she never got me checked for anything until 17.

Example: If the biological mother has ADHD then the child had anxiety is that the same thing?