Red blood cells have a protein that carries oxygen. Sickle cell anemia is a genetic disease that causes red blood cells to have an odd shape. The odd shape prevents the blood cells from carrying as much oxygen as they should. What is the most likely cause for this disease? 1) expression of additional RNA during transcription.
2) excessive cell division during mitosis.
3) failure to produce enough plasma to contain the oxygen.
4) a change in the proteins that express the normal trait.