¹Adli Bilimler Enstitüsü, Ankara Üniversitesi Tıp Fakültesi Cebeci Yerleşkesi, 06590, Dikimevi, Ankara DOI : 10.12991/mpj.201620227342 Hemoglobinopathies is one of the most extensive single gene disorders in the world and one of the most important type of these diseases, sickle cell disease (SCD) is an autosomal recessive inherited disorder of the red blood cells and affects many systems, is seen frequently both for the our country and for Mediterranean coastline region. The structure of the hemoglobin protein in patients with SCD is different when compared to healthy individuals. Patients with SCD have abnormal types of Hb, called mutant Hemoglobin S (HbS) protein and this protein is able to work as normal in an oxygenated environment. However, in an oxygen poor environment this protein may cause the shape change in red blood cells. In other words they take the form of elongated half moon or sickle shaped. The misshapen red cells can jam the tiny vessels as a result, imparing circulation and slows or stops the flow of blood. Vaso occlusive events result in tissue ischemia leading to organ damage and loss of organ function. On the other hand, repeated blood transfusions lead to iron overload in the tissues and organs of these patients. Therefore organs affected and functions are disrupted. Iron is a major component in the production and metabolism of free radicals in biological systems. Last studies indicate a significance of free radical mediated iron toxicity. In conclusion, free iron plays a crucial role in oxidative stress. In this review, detailed information about the pathophysiology, iron toxicity and distribution of sickle cell anemia will be given in Turkish population. Keywords : Sickle cell disease, Hemoglobin, Hemoglobin S, Iron; Iron toxicity