Heme synthesis(Fe) deficiency and DNA synthesis(B12, folate) deficiency can cause:

• A. Iron deficiency anemia
• B. Megaloblastic anemia
• C. Diminished erythropoiesis anemia
• D. Pernicious anemia

Answer: (C)

Both iron deficiency and B12/folate deficiency reduce red blood cell production in the bone marrow, but by different mechanisms. Iron deficiency limits heme synthesis, so developing erythroid cells can’t form hemoglobin properly, slowing maturation and decreasing effective erythropoiesis. B12 and folate are needed for DNA synthesis; without them, erythroid precursors can’t complete division, become megaloblastic, and many are destroyed in the marrow, also lowering erythropoiesis. The shared outcome is a reduced production of red cells, i.e., diminished erythropoiesis anemia. (Iron deficiency causes microcytic anemia, B12/folate deficiency causes macrocytic/megaloblastic anemia, and pernicious anemia is a B12 deficiency cause, not a separate mechanism here.)