Sickle cell anaemia (SCA) is a genetic blood disorder that affects the structure of haemoglobin, a protein present in red blood cells which carries oxygen throughout the body. Structural abnormality of haemoglobin causes the red blood cells to become deformed and attain the shape of a sickle. The sickle-shaped red blood cells cannot function properly and undergo premature death. This leads to anaemia SCA is caused by the mutation of HBB gene. The HBB gene is responsible for the production of beta-globin, an important protein in haemoglobin. If HBB gene undergoes mutation, an abnormal beta-globin is produced which is also known as haemoglobin S (HbS). This abnormal beta-globin distorts the red blood cells into a sickle shape.