Thalassemia is an inherited blood disorder that is passed from parents to their children and affects the body's ability to produce normal haemoglobin. It occurs when there is an abnormality or mutation in one of the genes involved in haemoglobin production. Haemoglobin is the protein molecule that enables red blood cells to carry oxygen throughout the body. People with thalassemia produce fewer healthy haemoglobin, i.e. RBCs lasts for a shorter period of time, resulting in inadequate healthy red blood cells travelling in the bloodstream.