Sickle cell anaemia, often called sickle cell disease or sickle cell disorder, is a term covering a number of similar conditions that affect haemoglobin. It has been described as the most common genetic disorder and affects around 12,500 people in the UK, predominantly of African and Afro-Caribbean descent. The severity of the physical, psychological and social consequences of this cluster of disorders can be greatly reduced if families who are affected receive early diagnosis, appropriate support, advice and care.