A novel FLCN mutation in family members diagnosed with primary spontaneous pneumothorax.

Background: Primary spontaneous pneumothorax (PSP) is a disease characterized by the accumulation of air in the pleural space between the lung and thoracic wall. It is more common in young, tall, thin, and asthenic men. A family history was reported for approximately 11.5% of individuals admitted with PSP. The literature has reported cases diagnosed with familial PSP, who have no manifestations of Birt-Hogg-Dubé (BHD) syndrome but mutations in different exons of the Folliculin (FLCN) gene. The aim of this study is to present a Turkish family in which 13 members from three generations of the same family developed recurrent isolated spontaneous pneumothorax with a novel mutation in the FLCN.

Methods: A male proband was diagnosed with spontaneous pneumothorax in the emergency department of the University of Health Sciences Haydarpasa Numune Training and Research Center, Istanbul, Turkey. His 12 relatives from three generations diagnosed with PSP, as revealed by his family history, were invited to the hospital to give blood samples for mutation analysis. The Sanger sequence data of FLCN were analyzed on the ENSEMBL website using SeqScape 3 and Codon Aligner software.

Results: A novel heterozygous mutation c. 1273C>T (p.Gln425Ter) was detected in exon 11 of the FLCN, which caused PSP in the proband and his 12 relatives tested using Sanger sequencing.

Conclusion: We found that a heterozygous mutation in exon 11 of FLCN c. 1273C>T (p.Gln425Ter), which was identified for the first time in our study, might cause isolated familial spontaneous pneumothorax.