Birt Hogg Dubé syndrome and the FLCN gene
Birt Hogg Dubé syndrome (BHD) is an inherited syndrome caused by a mutation in the Folliculin gene (FLCN). It is very rare, with around 400 families known worldwide.
Individuals with BHD almost always develop small skin coloured lumps on the face and chest (benign skin tumours called fibrofolliculoma) which appear in the 20s. (You can see some examples here. Individuals with BHD have a high chance of developing cysts in the lungs and the kidneys.
Kidney tumours occur in 20 to 30% of individuals. These tend to be bilateral, multifocal and slow growing. In some cases, these tumours may develop into cancers. Screening for renal tumours should start at age 20 with an abdominal MRI, followed by annual high quality renal ultrasound.
The severity of the signs and symptoms vary among affected individuals, even within families, and is not predictable.
Because of the risk of spontaneous pneumothorax (a "collapsed lung"), a medicalert bracelet should be worn. Smoking and scuba diving (due to high ambient pressures) should be avoided.
There is a 50% chance of a person who carries a germline FLCN mutation, whether male or female, passing the mutation to their son or daughter. If a mutation is identified, then predictive testing is available for blood relatives. However, as current genetic testing does not identify a mutation in all individuals who meets the clinical diagnosis of Birt Hogg Dubé syndrome, their first-degree relatives (parents, siblings and children) should have at least baseline screening from age 20.
Does this sound like you or your family? Has an FLCN mutation been detected in a blood relative? Make an appointment with Dr Hilda High at Sydney Cancer Genetics. It is a confidential opportunity to discuss your personal and family history of cancer and genetic testing can be organised, if needed.
These links may be useful
- We haven't found a specific Australian Support Group for this syndrome yet. However, BHD Foundation is based in London and has good resources.
- The Cancer Genetics section of the Cancer Institute's eviQ website provides up-to-date Australian-based management guidelines
- The US National Library of Medicine website has more information about this syndrome.