Antonyms of adopted:
native, connatural, inbred, inborn.
Examples of usage:
  1. Very quietly, too, it had travelled to its adopted country.
    "The Story of a Dewdrop", J. R. Macduff.
  2. After considerable discussion this plan was adopted.
    "La Vendée An Historical Romance", Anthony Trollope.
  3. Common sense has adopted them.
    "The Flutter of the Goldleaf; and Other Plays", Olive Tilford Dargan and Frederick Peterson.