Sickle-cell disease (SCD), or sickle-cell anaemia (or anemia; SCA) or drepanocytosis, is an autosomal co-dominant genetic blood disorder characterized by red blood cells that assume an abnormal, rigid, sickle shape. Sickling decreases the cells’ flexibility and results in a risk of various complications. The sickling occurs because of a mutation in the haemoglobin gene. Life expectancy is shortened, with studies reporting an average life expectancy of 42 in males and 48 in females.