Interestingly, while each of the above syndromes is subtype-specific, BHD syndrome predisposes to developing all subtypes of RCCs 10, which indicates that these syndromes have diverse genetic and pathogenic backgrounds in renal tumorigenesis 14, and only FLCN plays a role of universal renal tumor suppressor. This evidence concerns the gene FLCN and Birt-Hogg-Dubé syndrome.