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Up to 20% of idiopathic interstitial lung disease is familial, referred to as Familial Pulmonary Fibrosis (FPF). We performed an integrated analysis of FPF genetic risk by comprehensively evaluating for genetic rare variants (RVs) in a large cohort of FPF kindreds.We performed whole-exome sequencing and/or candidate gene sequencing from affected individuals in 569 FPF kindreds, followed by co-segregation analysis in large kindreds, gene burden analysis, gene-based risk scoring, cell type enrichment analysis, and co-expression network construction.We found that 14.9% - 23.4% of genetic risk in kindreds could be explained by RVs in genes previously linked to FPF, predominantly telomere related genes. We identified new candidate genes in a small number of families, including SYDE1, SERPINB8, GPR87, and NETO1, and developed tools for evaluation and prioritization of RV-containing genes across kindreds. Several pathways were enriched for RV-containing genes in FPF, including focal adhesion and mitochondrial complex I assembly. By combining single cell transcriptomics with prioritized candidate genes, we discovered that expression of RV-containing genes was enriched in smooth muscle cells, type II alveolar epithelial cells, and endothelial cells.In the most comprehensive FPF genetic study to date, we defined the prevalence of RVs in known FPF-related genes and identified new candidate genes and pathways relevant to FPF. However, we did not identify new RV-containing genes shared across multiple kindreds, thereby suggesting that heterogeneous genetic variants involving a variety of genes and pathways mediate genetic risk in most FPF kindreds.

Aging is a major risk factor to develop neurodegenerative diseases and is associated with decreased buffering capacity of the proteostasis network. We investigated the significance of the unfolded protein response (UPR), a major signaling pathway activated to cope with endoplasmic reticulum (ER) stress, in the functional deterioration of the mammalian brain during aging. We report that genetic disruption of the ER stress sensor IRE1 accelerated age-related cognitive decline. In mouse models, overexpressing an active form of the UPR transcription factor XBP1 restored synaptic and cognitive function, in addition to reducing cell senescence. Proteomic profiling of hippocampal tissue showed that XBP1 expression significantly restore changes associated with aging, including factors involved in synaptic function and pathways linked to neurodegenerative diseases. The genes modified by XBP1 in the aged hippocampus where also altered. Collectively, our results demonstrate that strategies to manipulate the UPR in mammals may help sustain healthy brain aging.

Emerging knowledge indicates the difficulty in categorizing unusual cystic fibrosis (CF) mutations, with regard to both pathogenic mechanism and theratype. As case in point, we present data concerning P67L mutation of the cystic fibrosis transmembrane conductance regulator (CFTR), a defect carried by a small number of individuals with CF and sometimes attributed to a channel conductance abnormality. Findings from our laboratory and others establish that P67L causes protein misfolding, disrupts maturation, confers gating defects, is thermally stable, and exhibits near normal conductance. These results provide one framework by which rare CF alleles such as P67L can be more comprehensively profiled vis-a-vis molecular pathogenesis. We also demonstrate that emerging CF treatments - ivacaftor and lumacaftor - can mediate pronounced pharmacologic activation of P67L CFTR. Infrequent CF alleles are often improperly characterized, in part, due to the small numbers of patients involved. Moreover, access to new personalized treatments among patients with ultra-orphan genotypes has been limited by difficulty arranging phase III clinical trials, and off-label prescribing has been impaired by high drug cost and difficulty arranging third party reimbursement. Rare CFTR mutations such as P67L are emblematic of the challenges to "precision" medicine, including use of the best available mechanistic knowledge to treat patients with unusual forms of disease.