FANCC-Associated Fanconi Anemia
What Your Test Results Mean:
Carriers typically show no symptoms of FANCC-associated FA; however, carriers are at an increased risk of having a child with FANCC-associated FA. Risk for the current or future pregnancies is dependent on your partner’s carrier status.
Disease Explained:
FANCC-associated FA is an inherited disorder characterized by a broad range of physical abnormalities, progressive bone marrow failure, and increased risk of cancer. Physical abnormalities, found in 75% of individuals with this condition, are typically present at birth and commonly include short stature, upper limb abnormalities, and hyperpigmentation of the skin. Hematologic complications of FA typically occur within the first decade of life but are highly variable. Cancer risk remains a concern throughout the lifespan. Individuals with FA are not able to properly repair DNA damage due to defects in the FANCC gene leading to premature cell death or uncontrolled cell growth.
Monitoring for evidence of bone marrow failure and solid tumors as well as growth and development is recommended surveillance for individuals with FA. Treatment is generally symptomatic; however, some individuals undergo hematopoietic stem cell transplantation to cure the hematologic manifestations of FA. Stem call transplant does not reduce and may increase the risk of solid tumors. The majority of individuals with FA reach adulthood. Lifespan is variable with median age of death in the 30s.
How the Genetics Works:
There are at least 16 genes associated with Fanconi anemia. This testing identifies pathogenic variants in one of these genes, FANCC. Variants in this gene cause approximately 14% of Fanconi anemia. The clinical features of FANCC-associated FA are caused by variants in the FANCC gene. Individuals have two copies of the FANCC gene. Carriers have a single variant in the FANCC gene while individuals with FANCC-associated FA have variants in both copies of FANCC, one inherited from each parent.