What is fanconi anaemia?

Fanconi anaemia is a complex medical condition that may affect many parts of the body. People with this condition may have bone marrow failure, physical abnormalities, organ defects, and an increased risk of certain cancers.

People with fanconi anaemia may also develop myelodysplastic syndrome (MDS), a condition in which immature blood cells fail to develop normally.

What are the symptoms?

More than 50% of people with fanconi anaemia have physical abnormalities. These abnormalities can involve irregular skin colouring such as unusually light-coloured skin (hypopigmentation) or café-au-lait spots, which are flat patches on the skin that are darker than the surrounding area.

Other possible symptoms include malformed thumbs or forearms and other skeletal problems including short stature, malformed or absent kidneys, gastrointestinal abnormalities, heart defects, eye abnormalities such as small or abnormally shaped eyes, malformed ears and hearing loss.

Additional signs and symptoms can include abnormalities of the brain and the central nervous system, including increased fluid in the centre of the brain or an unusually small head size.

Individuals with fanconi anaemia have an increased risk of developing a cancer of blood-forming cells in the bone marrow called acute myeloid leukaemia (AML).

What causes fanconi anaemia?

Fanconi anaemia is an inherited genetic condition. Scientists have now discovered 15 FA or FA-like genes [A, B, C, D1 (BRCA2), D2, E, F, G, I, J, L, M, N, P and RAD51C]. These genes account for more than 95% of fanconi anaemia cases. Some patients do not appear to have mutations in any of the 15 genes, suggesting that more genes are yet to be discovered.

Who does fanconi anaemia affect?

Fanconi anaemia is rare and occurs in 1 in 160,000 individuals worldwide. This condition is more common among people of Ashkenazi Jewish descent, the Roma population of Spain, and black South Africans.

Links to aplastic anaemia

Approximately 90% of people with fanconi anaemia have impaired bone marrow function that leads to a decrease in the production of all blood cells – aplastic anaemia.

What is the diagnosis?

Physical problems present at birth may indicate fanconi anaemia. However, sometimes AML is the first sign of the condition. Blood tests will reveal low counts of all types of blood cells – red, white cells and platelets. The main diagnostic test for is called a chromosome breakage test, in which a patient's DNA is placed in a test tube with a chemical that damages it. Normal cells are able to correct most of the damage, whereas cells from somebody with fanconi anaemia are significantly damaged.

What does the treatment entail?

Some abnormalities, particularly abnormal thumbs, skin tags, or heart defects, may require surgery. Aplastic anaemia often responds to administration of the androgenic steroids oxymetholone or Danazol, although the beneficial effect is not permanent and side effects are common.

Bone marrow transplantation can cure blood problems, but there can be severe complications. The best results have been in children with tissue-matched sibling donors who are themselves free of the condition.

Encouragingly, results from matched unrelated donors are improving. There is also ongoing research into whether gene therapy can play a role in future treatment. Regular examinations are necessary to watch for signs of leukaemia or cancer.

How can you get help?

You can get emotional support and information from the Fanconi Hope organisation.