Publications by authors named "Gaedigk A"

The widely prescribed oral anti-diabetic drug metformin is eliminated unchanged in the urine primarily through active tubular secretion. This process is mediated by organic cation transporter 2 (OCT2), an uptake transporter expressed on the basolateral membrane of renal proximal tubule cells. Metformin uptake into the liver, the site of action, is mediated by OCT1, which is expressed on the sinusoidal membrane of hepatocytes.

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Few biological or clinical predictors guide medication selection and/or dosing for attention-deficit/hyperactivity disorder (ADHD). Accumulating data suggest that genetic factors may contribute to clinically relevant pharmacodynamic (e.g.

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Background: testing is increasingly used to guide drug therapy and thus, reliable methods are needed to test this complex and polymorphic gene locus. A particular challenge arises from the detection and interpretation of structural variants (SVs) including gene deletions, duplications, and hybrids with the pseudogene. This study validated the Absolute Q platform for digital PCR-based copy number variation (CNV) determination by comparing results to those obtained with a previously established method using the QX200 platform.

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The Pharmacogene Variation Consortium (PharmVar) serves as a global repository providing star (*) allele nomenclature for the polymorphic human CYP4F2 gene. CYP4F2 genetic variation impacts the metabolism of vitamin K, which is associated with warfarin dose requirements, and the metabolism of drugs, such as imatinib or fingolimod, and certain endogenous compounds including vitamin E and eicosanoids. This GeneFocus provides a comprehensive overview and summary of CYP4F2 genetic variation including the characterization of 14 novel star alleles, CYP4F2*4 through *17.

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The Pharmacogene Variation Consortium (PharmVar) provides nomenclature for the human CYP2A gene locus containing the highly polymorphic CYP2A6 gene. CYP2A6 plays a role in the metabolism of nicotine and various drugs. Thus, genetic variation can substantially contribute to the function of this enzyme and associated efficacy and safety.

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  • - The DPYD gene is crucial for encoding dihydropyrimidine dehydrogenase (DPD), which helps metabolize drugs like 5-fluorouracil used in cancer treatment; reduced DPD activity can lead to severe side effects in patients.
  • - To improve pharmacogenetic testing for DPYD, a collaboration among various organizations created and distributed 33 characterized DNA samples from Coriell cell lines to different laboratories for testing.
  • - These samples allowed the identification of 33 distinct DPYD variants and are intended to enhance quality assurance and control in clinical testing for better patient safety in cancer treatment.
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  • The Association for Molecular Pathology's Pharmacogenomics Working Group aims to establish key attributes and a standard set of genetic variants for clinical pharmacogenetic testing.
  • The document outlines two tiers of recommended genetic variants, which will guide clinical laboratories in creating pharmacogenomics assays.
  • Focused on dihydropyrimidine dehydrogenase (DPYD) testing, the recommendations encourage standardization while serving as a flexible reference rather than strict rules.
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Beta-blockers are widely used medications for a variety of indications, including heart failure, myocardial infarction, cardiac arrhythmias, and hypertension. Genetic variability in pharmacokinetic (e.g.

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Methadone is a mu (μ) opioid receptor agonist used clinically in adults and children to manage opioid use disorder, neonatal abstinence syndrome, and acute and chronic pain. It is typically marketed as a racemic mixture of R- and S-enantiomers. R-methadone has 30-to 50-fold higher analgesic potency than S-methadone, and S-methadone has a greater adverse effect (prolongation) on the cardiac QTc interval.

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  • This report analyzes the effects of a new CYP2C haplotype (CYP2C:TG) on how proton pump inhibitors (PPIs) are metabolized in children.
  • The study involved 41 children aged 6-21 and examined how the CYP2C:TG allele interacts with the CYP2C19 gene, which is important for PPI metabolism.
  • Results showed that the CYP2C:TG haplotype does not significantly affect PPI metabolism, indicating that routine testing for this haplotype is not necessary for adjusting PPI dosages in children.
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  • A clinical study assessed how the genetic variant c.521T>C (rs4149056) affects atorvastatin levels in children and adolescents (ages 8-21) with high cholesterol, focusing on different genotypes.
  • Results showed that participants with the c.521T/C and c.521C/C variants had significantly higher plasma atorvastatin concentrations than those with the c.521T/T genotype, suggesting a possible genetic influence on drug metabolism.
  • The study found that this genetic variant explained about 65% of the variability in atorvastatin exposure, indicating the importance of personalizing dosage to avoid potential risks of toxicity, especially considering factors like body mass index.
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The DPYD gene encodes dihydropyrimidine dehydrogenase, the rate-limiting enzyme for the metabolism of fluoropyrimidines 5-fluorouracil and capecitabine. Genetic variants in DPYD have been associated with altered enzyme activity, therefore accurate detection and interpretation is critical to predict metabolizer status for individualized fluoropyrimidine therapy. The most commonly observed deleterious variation is the causal variant linked to the previously described HapB3 haplotype, c.

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The Pharmacogene Variation Consortium (PharmVar) provides nomenclature for the highly polymorphic human CYP2D6 gene locus and a comprehensive summary of structural variation. CYP2D6 contributes to the metabolism of numerous drugs and, thus, genetic variation in its gene impacts drug efficacy and safety. To accurately predict a patient's CYP2D6 phenotype, testing must include structural variants including gene deletions, duplications, hybrid genes, and combinations thereof.

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Antimalarial primaquine (PQ) eliminates liver hypnozoites of   gene variation contributes to PQ therapeutic failure. Additional gene variation may contribute to PQ efficacy. Information on pharmacogenomic variation in Madagascar, with malaria and a unique population admixture, is scanty.

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A novel haplotype composed of two non-coding variants, CYP2C18 NM_000772.3:c.*31T (rs2860840) and NM_000772.

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Article Synopsis
  • Complex regions in the human genome like repeat motifs and structural variations complicate genetic analysis, especially using short-read sequencing technologies.
  • A novel PCR-free CRISPR-Cas9 method was developed for long-read sequencing, effectively characterizing a significant pharmacogene and its associated pseudogenes across different populations.
  • This technique enables high-resolution genotyping, leading to better understanding of enzyme activity and drug responses, particularly benefiting underrepresented populations in clinical settings.
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The goals of the Association for Molecular Pathology Clinical Practice Committee's Pharmacogenomics (PGx) Working Group are to define the key attributes of pharmacogenetic alleles recommended for clinical testing and a minimum set of variants that should be included in clinical PGx genotyping assays. This document series provides recommendations for a minimum panel of variant alleles (tier 1) and an extended panel of variant alleles (tier 2) that will aid clinical laboratories when designing assays for PGx testing. The Association for Molecular Pathology PGx Working Group considered functional impact of the variant alleles, allele frequencies in multiethnic populations, the availability of reference materials, and other technical considerations for PGx testing when developing these recommendations.

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  • Pharmacogenetic testing for CYP3A4 is expanding, but there's a lack of quality control materials for many variants.
  • The CDC and Coriell Institute teamed up to analyze 30 DNA samples to identify various CYP3A4 alleles, including a new one, CYP3A4∗38.
  • These characterized DNA samples will help clinical labs improve their testing quality and create reliable reference materials for pharmacogenetic testing.
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Serotonin reuptake inhibitor antidepressants, including selective serotonin reuptake inhibitors (SSRIs; i.e., citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline), serotonin and norepinephrine reuptake inhibitors (i.

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Over 20% of US Food and Drug Administration (FDA)-approved drugs in the United States are metabolized by the hepatic enzyme cytochrome P450 2D6 (CYP2D6). The gene encoding CYP2D6 is highly polymorphic and genetic variation has been shown to impact drug response for many commonly dispensed drugs including opioids and antidepressants. Thus, it is important to understand an individual's CYP2D6 metabolizer status to optimize treatment outcomes for patients taking medications that are metabolized by this enzyme.

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Pharmacogenomic (PGx) testing may increase the probability of remission and response in patients with major depressive disorder (MDD) undergoing pharmacotherapy. Given the potential implications of these outcomes and recent proliferation of PGx studies, we conducted a systematic review to evaluate the effectiveness of PGx testing on clinical outcomes in patients with MDD as compared to treatment as usual (TAU). MEDLINE, Embase, PsycInfo, and CENTRAL were searched for English-language articles from 2000 to 2021 for randomized controlled trials (RCTs) comparing PGx-guided treatment vs.

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The goal of this study was to determine whether CYP2D6 metabolizer status within the ondansetron-treated pediatric tonsillectomy population is associated with risk of postoperative nausea and vomiting (PONV) in the post-anesthesia care unit. We conducted a retrospective cohort study of pediatric patients (<18 years) who underwent tonsillectomy and received ondansetron on the day of the procedure. Data were obtained from BioVU, an institutional biobank that links DNA to de-identified electronic health record data.

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