Publications by authors named "Garry R Cutting"

Article Synopsis
  • - Pseudohypoparathyroidism type 1B (PHP1B) is caused by epigenetic changes affecting the GNAS gene, leading to parathyroid hormone resistance, especially in kidney cells due to inhibited Gsα protein expression from the maternal allele.
  • - Genetic defects in PHP1B patients include loss of methylation in specific regions and additional methylation issues in some, prompting researchers to identify the genetic basis for autosomal dominant PHP1B in families with complex GNAS methylation problems.
  • - Genome sequencing highlighted small GNAS variants and a microdeletion in affected families that possibly alter AS transcript expression, leading to reduced NESP transcription, thus suggesting a mechanism behind PHP1B development.
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To identify modifier loci underlying variation in body mass index (BMI) in persons with cystic fibrosis (pwCF), we performed a genome-wide association study (GWAS). Utilizing longitudinal height and weight data, along with demographic information and covariates from 4,393 pwCF, we calculated AvgBMIz representing the average of per-quarter BMI Z scores. The GWAS incorporated 9.

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Non-viral nanoparticles (NPs) have seen heightened interest as a delivery method for a variety of clinically relevant nucleic acid cargoes in recent years. While much of the focus has been on lipid NPs, non-lipid NPs, including polymeric NPs, have the possibility of improved efficacy, safety, and targeting, especially to non-liver organs following systemic administration. A safe and effective systemic approach for intracellular delivery to the lungs could overcome limitations to intratracheal/intranasal delivery of NPs and improve clinical benefit for a range of diseases including cystic fibrosis.

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We broaden the clinical versatility of human nasal epithelial (HNE) cells. HNEs were isolated from 10 participants harboring () variants: 9 with rare variants (Q359R [=2], G480S, R334W [=5], and R560T) and 1 harboring R117H;7T;TG10/5T;TG12. Cultures were differentiated at the air-liquid interface.

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Article Synopsis
  • The study examines sweat glands' ion transport in cystic fibrosis (CF) to better understand the relationship between sweat chloride levels, CFTR gene variations, and lung health.
  • Researchers developed a new technique for culturing eccrine sweat gland (ESG) cells and analyzed their function using cutting-edge sequencing methods.
  • Results show that ESGs from non-CF donors had effective ion transport, while those from CF patients displayed varying CFTR function depending on their specific gene mutations, illustrating the importance of genotype in disease severity and treatment response.
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Background: Cystic fibrosis (CF) is caused by deleterious variants in each CFTR gene. We investigated the utility of whole-gene CFTR sequencing when fewer than two pathogenic or likely pathogenic (P/LP) variants were detected by conventional testing (sequencing of exons and flanking introns) of CFTR.

Methods: Individuals with features of CF and a CF-diagnostic sweat chloride concentration with zero or one P/LP variants identified by conventional testing enrolled in the CF Mutation Analysis Program (MAP) underwent whole-gene CFTR sequencing.

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Since genotype imputation was introduced, researchers have been relying on the estimated imputation quality from imputation software to perform post-imputation quality control (QC). However, this quality estimate (denoted as Rsq) performs less well for lower-frequency variants. We recently published MagicalRsq, a machine-learning-based imputation quality calibration, which leverages additional typed markers from the same cohort and outperforms Rsq as a QC metric.

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Article Synopsis
  • - The study aims to uncover genetic factors contributing to severe cystic fibrosis liver disease (CFLD) since it affects only about 7% of individuals with cystic fibrosis (CF).
  • - Researchers analyzed whole-genome sequencing data from over 4,000 CF patients, finding significant associations with specific genetic variants related to CFLD, including the Z allele of SERPINA1 and several other genes.
  • - The findings suggest that severe CFLD is linked to various biological pathways, such as inflammation, immune response, and liver cell signaling, potentially leading to better understanding and treatment methods for the condition.
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Background: In 2017, the US Food and Drug Administration initiated expansion of drug labels for the treatment of cystic fibrosis (CF) to include CF transmembrane conductance regulator (CFTR) gene variants based on in vitro functional studies. This study aims to identify CFTR variants that result in increased chloride (Cl) transport function by the CFTR protein after treatment with the CFTR modulator combination elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA). These data may benefit people with CF (pwCF) who are not currently eligible for modulator therapies.

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Some residues in the cystic fibrosis transmembrane conductance regulator (CFTR) channel are the site of more than one CFTR variant that cause cystic fibrosis. Here, we investigated the function of S1159F and S1159P, two variants associated with different clinical phenotypes, which affect the same pore-lining residue in transmembrane segment 12 that are both strongly potentiated by ivacaftor when expressed in CFBE41o bronchial epithelial cells. To study the single-channel behaviour of CFTR, we applied the patch-clamp technique to Chinese hamster ovary cells heterologously expressing CFTR variants incubated at 27°C to enhance channel residence at the plasma membrane.

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Small molecule drugs known as modulators can treat ~90% of people with cystic fibrosis (CF), but do not work for premature termination codon variants such as W1282X (c.3846G>A). Here we evaluated two gene editing strategies, Adenine Base Editing (ABE) to correct W1282X, and Homology-Independent Targeted Integration (HITI) of a CFTR superexon comprising exons 23-27 (SE23-27) to enable expression of a CFTR mRNA without W1282X.

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Canonical splice site variants affecting the 5' GT and 3' AG nucleotides of introns result in severe missplicing and account for about 10% of disease-causing genomic alterations. Treatment of such variants has proven challenging due to the unstable mRNA or protein isoforms that typically result from disruption of these sites. Here, we investigate CRISPR-Cas9-mediated adenine base editing for such variants in the cystic fibrosis transmembrane conductance regulator () gene.

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Adeno-associated virus (AAV) vector has shown multiple clinical breakthroughs, but its clinical implementation in inhaled gene therapy remains elusive due to difficulty in transducing lung airway cells. We demonstrate here AAV serotype 6 (AAV6) associated with extracellular vesicles (EVs) and secreted from vector-producing HEK-293 cells during vector preparation (EVAAV6) as a safe and highly efficacious gene delivery platform for inhaled gene therapy applications. Specifically, we discovered that EVAAV6 provided markedly enhanced reporter transgene expression in mucus-covered air-liquid interface (ALI) cultures of primary human bronchial and nasal epithelial cells as well as in mouse lung airways compared to standard preparations of AAV6 alone.

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Lung disease is the major cause of morbidity and mortality in persons with cystic fibrosis (pwCF). Variability in CF lung disease has substantial non-CFTR (CF transmembrane conductance regulator) genetic influence. Identification of genetic modifiers has prognostic and therapeutic importance.

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Cystic fibrosis (CF) is a multiorgan disease caused by a wide variety of mutations in the cystic fibrosis transmembrane conductance regulator gene. As treatment has progressed from symptom mitigation to targeting of specific molecular defects, genetics has played an important role in identifying the proper precision therapies for each individual. Novel therapeutic approaches are focused on expanding treatment to a greater number of individuals as well as working toward a cure.

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Article Synopsis
  • - Individuals with cystic fibrosis (CF) can develop complications like cystic fibrosis-related diabetes (CFRD) and meconium ileus (MI), which are influenced by genetic factors beyond the CFTR gene.
  • - A study using whole-genome sequencing identified 11 genetic variants linked to MI and 12 to CFRD, with some variants (like those in SLC26A9, CEBPB, and PRSS1) affecting both conditions.
  • - While some genetic loci increase the risk for both CFRD and MI, others specifically impact one condition, suggesting both differences and shared genetic mechanisms between these complications.
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Whole-genome sequencing (WGS) is the gold standard for fully characterizing genetic variation but is still prohibitively expensive for large samples. To reduce costs, many studies sequence only a subset of individuals or genomic regions, and genotype imputation is used to infer genotypes for the remaining individuals or regions without sequencing data. However, not all variants can be well imputed, and the current state-of-the-art imputation quality metric, denoted as standard Rsq, is poorly calibrated for lower-frequency variants.

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In December 2020, the U.S. Food and Drug Administration (FDA) expanded the list of CFTR variants approved for treatment with CFTR modulators drugs from 39 to 183.

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The chloride channel dysfunction caused by deleterious cystic fibrosis transmembrane conductance regulator (CFTR) variants generally correlates with severity of cystic fibrosis (CF). However, 3 adults bearing the common severe variant p.Phe508del (legacy: F508del) and a deletion variant in an ivacaftor binding region of CFTR (p.

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Cystic fibrosis (CF) is a severe genetic disorder that can cause multiple comorbidities affecting the lungs, the pancreas, the luminal digestive system and beyond. In our previous genome-wide association studies (GWAS), we genotyped approximately 8,000 CF samples using a mixture of different genotyping platforms. More recently, the Cystic Fibrosis Genome Project (CFGP) performed deep (approximately 30×) whole genome sequencing (WGS) of 5,095 samples to better understand the genetic mechanisms underlying clinical heterogeneity among patients with CF.

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Introduction: Loss-of-function variants in both copies of the cystic fibrosis transmembrane conductance regulator () gene cause cystic fibrosis (CF); however, there is evidence that reduction in CFTR function due to the presence of one deleterious variant can have clinical consequences. Here, we hypothesise that variants in individuals with a history of smoking are associated with chronic obstructive pulmonary disease (COPD) and related phenotypes.

Methods: Whole-genome sequencing was performed through the National Heart, Lung, and Blood Institute TOPMed (TransOmics in Precision Medicine) programme in 8597 subjects from the COPDGene (Genetic Epidemiology of COPD) study, an observational study of current and former smokers.

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Purpose: The growing size of public variant repositories prompted us to test the accuracy of pathogenicity prediction of DNA variants using population data alone.

Methods: Under the a priori assumption that the ratio of the prevalence of variants in healthy population vs that in affected populations form 2 distinct distributions (pathogenic and benign), we used a Bayesian method to assign probability to a variant belonging to either distribution.

Results: The approach, termed Bayesian prevalence ratio (BayPR), accurately parsed 300 of 313 expertly curated CFTR variants: 284 of 296 pathogenic/likely pathogenic variants in 1 distribution and 16 of 17 benign/likely benign variants in another.

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Background: Cystic fibrosis (CF) is a recessive condition caused by variants in each CF transmembrane conductance regulator (CFTR) allele. Clinically affected individuals without two identified causal variants typically have no further interrogation of CFTR beyond examination of coding regions, but the development of variant-specific CFTR-targeted treatments necessitates complete understanding of CFTR genotype.

Methods: Whole genome sequences were analyzed on 5,058 individuals with CF.

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