Exome Sequencing Reveals Immune Genes as Susceptibility Modifiers in Individuals with α1-Antitrypsin Deficiency

Sci Rep. 2019 Sep 11;9(1):13088. doi: 10.1038/s41598-019-49409-1.

Abstract

Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder associated to early onset emphysema, mainly imputable to Pi*ZZ genotype. In spite of the serious potential effects, many AATD individuals do not develop emphysema. To identify genes/variants potentially involved in emphysema development we studied 4 AATD families. Each family had at least one affected sibling with emphysema and one non-affected. Whole Exome Sequencing (WES) was performed on genomic DNA isolated from 9 individuals with AATD (4 affected/5 non-affected). Genetic variants confirmed at least in three families were prioritized using QueryOR and network analysis was used to verify enriched pathways. In affected subjects: 14 genes (57% immune-related) segregated in a recessive model and 21 (29% immune-related) in a dominant model. In non-affected subjects: 21 genes (43% immune-related) segregated in a recessive model and 50 (24% immune-related) in a dominant model. In affected siblings immune genes had an activating function, while where immune-suppressing in non-affected siblings involving antigen processing, MHC-I presentation, TCR and PD-1 signalling. This study describes possible genetic susceptibility factors for emphysema development in AATD, and suggests that gene variants involved in regulation of immune homeostasis and maintenance of self-tolerance contribute to the development or suppression of the disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Exome Sequencing*
  • Female
  • Genetic Predisposition to Disease / genetics*
  • Humans
  • Male
  • Middle Aged
  • Molecular Sequence Annotation
  • alpha 1-Antitrypsin Deficiency / genetics*
  • alpha 1-Antitrypsin Deficiency / immunology*