Fanconi anemia is a severe genetic disorder with an autosomal recessive inheritance pattern.
This disease can occur in people of all ethnicities but has a higher frequency in certain populations. Fanconi anemia group C is more frequent in people of Ashkenazi Jewish descent. Group A is more frequent in people of North African Jewish descent, the Roma population in Spain, and South African people of Afrikaner descent.
The relevant gene mutation can be detected during genetic screening tests before conception. If both parents are found to be carriers of the mutation, they can choose to undergo IVF (in vitro fertilization) and test the embryos before transferring them to the womb.
Women who did not undergo preimplantation genetic diagnosis (PGD) and already have a child with this disorder, can undergo chorionic villus sampling in subsequent pregnancies, to test whether their unborn fetus is also a carrier of the gene mutation. If the fetus is found to carry the mutation, parents are usually recommended to terminate the pregnancy.
What are the symptoms?
Congenital defects appear in most people with this disease. The most common defects are missing thumbs. Other defects may include a small head (microcephaly), and smaller eyes caused by developmental delay in the womb.
Many people with this disease have skin pigmentation disorders, some also suffer from kidney malformations, and duodenal atresia. Some also suffer from mild intellectual disability and a short stature. However, around thirty percent of people with this disease are born with no birth defects.
The most important symptom is bone marrow failure. This gradual process begins during the first ten years of life and progresses until full bone marrow failure occurs by the age of forty.
The first sign of bone marrow failure is thrombocytopenia (low platelet count), followed by leukopenia (a decreased number or leukocytes), neutropenia (low number of neutrophils), and anemia.
During their twenties, people with this disease tend to develop bone marrow malignancies, with up to a third of patients developing hematological malignancy before age forty. In addition, patients are at an increased risk for developing tumors in the cervix, head, and neck area.