<prompt> Deficiency of the intrinsic factor of Castle causes:Microcytic anemiaPernicious anemiaCooleys anemiaAplastic anemia  <response>: Answer is B Pernicious Anemia Deficiency of Intrinsic factor leads to a specific form of vitamin B12 deficiency megaloblastic anemia called Pernicious Anemia. Pernicious Anemia also known as Addisons Anemia is a megaloblastic anemia due to deficiency of intrinsic factor secreted by parietal cells of gastric mucosa that is essential for vitamic B12 absorption. Note: Intrinsic factor was first described by castle coworkers and hence intrinsic factor is also called Intrinsic factor of Castle. 