In their new study, Rossing et al. (2016) have identified 13 different variants and 3 common polymorphism in the FLCN gene in 143 Danish patients with suspected BHD syndrome. 6 of these variants are novel, 9 are classified as pathogenic and 1 as likely pathogenic. Single nucleotide polymorphism (SNP) analysis revealed that a specific variant (c.1062+2T>G) is a founder mutation shared among all the Danish carriers. These findings contribute to extend our knowledge of the FLCN mutation spectrum.