Zhu et al. (2016) present the case of a Chinese family with four members with spontaneous pneumothorax but no skin or kidney symptoms. Birt-Hogg-Dube syndrome (BHD) is characterized by the development of skin papules, pneumothorax and kidney tumours. However, patients with BHD present heterogeneous phenotypes and familial spontaneous pneumothorax can occur without any skin or kidney manifestations. Genetic analysis revealed a novel heterozygous mutation c. 510C > G in exon 6 of the FLCN gene in the family members with spontaneous pneumothorax, but not in the healthy members, suggesting a strong correlation between the mutation and pneumothorax.