Recurrent primary spontaneous pneumothorax in a large Chinese family: a clinical and genetic investigation / 中华医学杂志(英文版)

BACKGROUND@#Primary spontaneous pneumothorax (PSP) is a common manifestation of Birt-Hogg-Dubé (BHD) syndrome, which is an autosomal dominant disorder caused by mutation of the folliculin (FLCN) gene. This study was established to investigate the mutation of the FLCN gene and the phenotype in a family with PSP.@*METHODS@#We investigated the clinical and genetic characteristics of a large Chinese family with recurrent spontaneous pneumothorax. Genetic testing was performed by Sanger sequencing of the coding exons (4-14 exons) of the FLCN gene.@*RESULTS@#Among ten affected members in a multi-generational PSP kindred, with a total of 18 episodes of spontaneous pneumothorax, the median age for the initial onset of pneumothorax was 42.5 years (interquartile range: 28.8-57.2 years). Chest computed tomography scan of the proband showed pulmonary cysts and pneumothorax. A novel nonsense mutation (c.1273C>T) in exon 11 of FLCN gene that leads to a pre-mature stop codon (p.Gln425*) was identified in the family. The genetic analysis confirmed the diagnosis of BHD syndrome in this family in the absence of skin lesions or renal tumors.@*CONCLUSIONS@#A novel nonsense mutation of FLCN gene was found in a large family with PSP in China. Our results expand the mutational spectrum of FLCN gene in patients with BHD syndrome.

Recurrent primary spontaneous pneumothorax in a large Chinese family: a clinical and genetic investigation / 中华医学杂志(英文版)

Background@#Primary spontaneous pneumothorax (PSP) is a common manifestation of Birt-Hogg-Dubé (BHD) syndrome, which is an autosomal dominant disorder caused by mutation of the folliculin (FLCN) gene. This study was established to investigate the mutation of the FLCN gene and the phenotype in a family with PSP.@*Methods@#We investigated the clinical and genetic characteristics of a large Chinese family with recurrent spontaneous pneumothorax. Genetic testing was performed by Sanger sequencing of the coding exons (4-14 exons) of the FLCN gene.@*Results@#Among ten affected members in a multi-generational PSP kindred, with a total of 18 episodes of spontaneous pneumothorax, the median age for the initial onset of pneumothorax was 42.5 years (interquartile range: 28.8-57.2 years). Chest computed tomography scan of the proband showed pulmonary cysts and pneumothorax. A novel nonsense mutation (c.1273C>T) in exon 11 of FLCN gene that leads to a pre-mature stop codon (p.Gln425*) was identified in the family. The genetic analysis confirmed the diagnosis of BHD syndrome in this family in the absence of skin lesions or renal tumors.@*Conclusions@#A novel nonsense mutation of FLCN gene was found in a large family with PSP in China. Our results expand the mutational spectrum of FLCN gene in patients with BHD syndrome.

A Rare Missense Variant in Telomerase Reverse Transcriptase is Associated with Idiopathic Pulmonary Fibrosis in a Chinese Han Family / 中华医学杂志(英文版)

<p><b>Background</b>Idiopathic pulmonary fibrosis (IPF) is an age-related and progressive interstitial lung disease. Up to 20% of cases of IPF cluster in families, genetic factors contribute significantly to the pathogenesis of the disease. This study aimed to explore the association between rare genetic variants and IPF in Chinese Han families.</p><p><b>Methods</b>A Han family, comprising three IPF patients and five unaffected their first-degree relatives, and 100 ethnically matched control individuals from North China were enrolled in this study. Peripheral blood was collected, and genomic DNA was extracted. To elucidate if rare genetic variants are associated with the familial IPF, we performed whole-exome sequencing of affected members from a Chinese Han IPF family. Candidate rare variants were then confirmed by Sanger sequencing.</p><p><b>Results</b>We identified a potentially damaging rare variant-a heterozygous mutation c.2146G>A in exon 6 of the gene encoding for telomerase reverse transcriptase (TERT), which results in an amino acid substitution (p.Ala716Thr). We confirmed the missense mutation by Sanger sequencing in all the affected family members but did not detect this mutation in 100 ethnically matched healthy controls. Patients carried this mutation were characterized by the frequently acute exacerbation of IPF phenotype, with poor prognosis. The mean time to death was 2.8 years after diagnosis.</p><p><b>Conclusion</b>Using next-generation sequencing technology in familial IPF patients, we identified the heterozygous rare variant in TERT gene, and strengthened the importance of genetic variants in telomere-related pathogenesis in Chinese IPF patients.</p>