What’s new in Birt–Hogg–Dubé syndrome?

Birt–Hogg–Dube syndrome (BHD) is a rare inherited condition, which predisposes to the development of benign hair follicle tumors called fibrofolliculomas, pneumothorax and kidney cancer. Lung and kidney cysts, respectively, are thought to cause the latter symptoms. The causative gene codes for a highly conserved protein called folliculin. Its function is still unknown, although recent data hint at a pervasive function in cellular signaling, affecting hypoxia responses and growth pathways. Because folliculin’s role in the cell is unclear, BHD symptoms are not well understood. Treatment, therefore, is still empirical. In this review, the authors summarize the current state of knowledge and report some of the most recent findings. The authors discuss the implications for pathogenesis and treatment of the cutaneous manifestations in BHD.