This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autoimmune Diseases, Subject name: Pathology
Which among the following is not an autoimmune disease? 
Select and explain. 
A. Myasthenia gravis, B. Systemic lupus erythematosus, C. Graves disease, D. Sickle cell disease
D: Sickle cell disease
Answer: D: Sickle cell disease 
Explanation: Ans. (d) Sickle cell diseaseRef: Robbin's pathology 9th ed. /211-15, 635* Sickle cell disease is a genetic condition which is characterized by mutation in beta globin chain of hemoglobin (glutamic acid is replaced with valine in the 6th position of beta chain).* Other given choices like SLE, Graves and MG are all autoimmune conditions.