Inactivating mutations in FLCN cause BHD syndrome which is characterized by facial fibrofolliculomas, pulmonary cysts, and pneumothorax and RCC.45, 59 The occurrence of fibrofolliculomas is age‐dependent and pneumothorax occurs in a minority of cases and so BHD may present with non‐syndromic RCC.60 However in the family reported herein, the t(10;17)(q11.21;p11.2) was associated with other evidence of BHD syndrome. The gene discussed is FLCN; the disease is pneumothorax.