Abstract
Birt-Hogg-Dubé (BHD) syndrome is a genetic disorder characterized by cutaneous fibrofolliculomas, lung cysts and kidney cancers. Affected individuals inherit germline mutations in the folliculin gene （FLCN）, which was identified by Nickerson et al. in 2002. Most individuals have multiple bilateral lung cysts. On the other hand, Japanese patients present with inconspicuous papules that do not lead them to a dermatologist. One third of individuals over 40 years of age develops kidney cancer. Since pathogenic FLCN variants are detectable by sanger sequencing analysis in around 90% of affected family members, definitive diagnosis of BHD syndrome is usually confirmed with genetic testing. We BHD-NET （http://www.bhd-net.jp/） update the latest information of the disease, respond to consultation by physicians, and support the affected families through exchange meetings.
