Early-onset emphysema in a large French-Canadian family: a genetic investigation

Publication date: Available online 15 April 2019Source: The Lancet Respiratory MedicineAuthor(s): Yohan Bossé, Maxime Lamontagne, Nathalie Gaudreault, Christine Racine, Marie-Hélène Levesque, Benjamin M Smith, Dominique Auger, Alisson Clemenceau, Marie-Ève Paré, Louis Laviolette, Victor Tremblay, Bruno Maranda, Mathieu C Morissette, François MaltaisSummaryBackgroundInherited mutations in SERPINA1 coding for the alpha-1 antitrypsin (A1AT) protein is the only well established cause of hereditary emphysema. We aimed to identify the genetic ecause of early-onset emphysema in a five-generation French-Canadian family free of A1AT deficiency.MethodsBetween Dec 1, 2014, and April 1, 2017, we investigated 63 individuals from a single pedigree, including 55 with DNA available. Whole-exome sequencing was done in a convenience sample of 14 individuals (nine with unambiguous expression of the typical form of emphysema observed in this family). We filtered rare non-synonymous variants that were predicted to be damaging to identify a single mutation in a biologically relevant gene shared among all affected individuals. We assessed segregation with the disease in additional family members who were not evaluated by whole-exome sequencing. The effect of the candidate variant on protein function was evaluated in vitro. mRNA and protein expression of the candidate gene was assessed in lung samples from unrelated individuals (n=80) with and without emphysema who underwent surgery for lung c...
Source: The Lancet Respiratory Medicine - Category: Respiratory Medicine Source Type: research