Publications by authors named "Olafsson I"

Monoclonal gammopathy of undetermined significance (MGUS) is the asymptomatic precursor of multiple myeloma and related diseases but has also been associated with thrombosis. Prior studies have not been based on screened cohorts leading to bias. We assessed the risk of thrombosis in a cohort of 75 422 individuals over 40 years old who were screened for MGUS in Iceland.

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Hypercalcemia in monoclonal gammopathy of undetermined significance (MGUS) presents a clinical challenge since it may indicate progression to multiple myeloma (MM) but could also be due to a multitude of unrelated disorders. To inform the approach to this clinical challenge, we conducted a nested cohort study within the iStopMM screening study. Of the 75,422 Icelanders aged 40 years and above who underwent screening for MGUS, we included 2,546 with MGUS who were in active follow-up, including regular serum calcium measurements.

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Light-chain (LC) monoclonal gammopathy of undetermined significance (MGUS) is a precursor of multiple myeloma (MM) and related conditions. LC-MGUS is characterized by free light-chain (FLC) levels outside defined reference intervals, indirectly indicating underlying plasma cell (PC) monoclonality. Next-generation flow cytometry (NGF) was used to evaluate clonal PC presence in bone marrow (BM) samples from individuals with LC-MGUS in the iStopMM study, aiming to assess the predictive value of the FLC ratio for clonal PC presence and its prognostic implications.

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Monoclonal gammopathy of undetermined significance (MGUS) is the precursor of multiple myeloma (MM) and related disorders. MGUS is characterized by asymptomatic paraproteinemia. In some cases, multiple paraproteins can be identified but the clinical implications of this phenomenon are poorly understood.

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Background: Signal transducer and activator of transcription 6 (STAT6) is central to type 2 (T2) inflammation, and common noncoding variants at the STAT6 locus associate with various T2 inflammatory traits, including diseases, and its pathway is widely targeted in asthma treatment.

Objective: We sought to test the association of a rare missense variant in STAT6, p.L406P, with T2 inflammatory traits, including the risk of asthma and allergic diseases, and to characterize its functional consequences in cell culture.

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Article Synopsis
  • Immunoglobulin G (IgG) is the primary type of antibody in human blood and exists in four subclasses (IgG1 to IgG4), which are influenced by specific genes.
  • A genome-wide association study involving 4,334 adults and 4,571 children identified ten new variants and confirmed four known variants linked to IgG subclass levels, affecting conditions like asthma and autoimmune diseases.
  • Significant links were found between certain genetic allotypes and specific IgG subclasses, with notable findings showing that lower IgG4 levels can both protect against childhood asthma and increase the risk of inflammatory bowel disease.
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Background: Monoclonal gammopathy of undetermined significance (MGUS) is a precursor of multiple myeloma (MM) and related conditions. In previous registry-based, retrospective studies, autoimmune diseases have been associated with MGUS. However, these studies were not based on a screened population and are therefore prone to ascertainment bias.

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  • Genome-wide association studies (GWASs) analyzed data from over 41,000 infertility cases and 687,000 controls, identifying 21 genetic risk loci for infertility, with 12 previously unreported.
  • The study found significant genetic correlations between female infertility and conditions like endometriosis and polycystic ovary syndrome, suggesting interactions between genetic risk factors.
  • Exome sequencing revealed that women with rare testosterone-lowering variants are at higher risk for infertility, yet no general correlation between reproductive hormones and infertility was found, highlighting a complex genetic landscape.
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Background: Monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) are asymptomatic precursor conditions to multiple myeloma and related disorders. Smoldering multiple myeloma is distinguished from MGUS by 10% or greater bone marrow plasma cells (BMPC) on sampling, has a higher risk for progression, and requires specialist management.

Objective: To develop a multivariable prediction model that predicts the probability that a person with presumed MGUS has 10% or greater BMPC (SMM or worse by bone marrow criteria) to inform the decision to obtain a bone marrow sample and compare its performance to the Mayo Clinic risk stratification model.

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  • X-chromosomal genetic variants can provide important information about differences in human traits and diseases between sexes.
  • A large-scale study analyzed kidney-related traits in nearly 909,000 individuals, finding 23 genetic loci linked to uric acid levels and estimated glomerular filtration rate (eGFR), including four new genes that may play a role in kidney function.
  • The research also discovered five novel sex-specific interactions, with variations showing different effects in males and females, and highlighted genes that are responsive to androgens (male hormones), indicating a complex relationship between sex and kidney-related genetics.
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There is some evidence that a prior cancer is a risk factor for the development of multiple myeloma (MM). If this is true, prior cancer should be associated with a higher prevalence or increased progression rate of monoclonal gammopathy of undetermined significance (MGUS), the precursor of MM and related disorders. Those with a history of cancer might therefore constitute a target population for MGUS screening.

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Importance: Recurrent pericarditis is a treatment challenge and often a debilitating condition. Drugs inhibiting interleukin 1 cytokines are a promising new treatment option, but their use is based on scarce biological evidence and clinical trials of modest sizes, and the contributions of innate and adaptive immune processes to the pathophysiology are incompletely understood.

Objective: To use human genomics, transcriptomics, and proteomics to shed light on the pathogenesis of pericarditis.

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  • Researchers conducted a study to identify genetic factors influencing the likelihood of women giving birth to spontaneous dizygotic (DZ) twins, uncovering four new loci: GNRH1, FSHR, ZFPM1, and IPO8, alongside previously known loci FSHB and SMAD3.
  • * The study involved a large genome-wide association meta-analysis (GWAMA) of over 700,000 participants, focusing on mothers of spontaneous DZ twins and their offspring, excluding cases from assisted reproductive technologies (ARTs).
  • * Findings indicate that the newly identified loci play roles in female reproduction, and significant correlations were found with various reproductive traits and body size, suggesting evolutionary pressures against DZ twinning in humans.
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Hemodilution of bone marrow (BM) aspirates is a limitation of multiparameter flow cytometry (MFC) in plasma cell disorders. There is a need for a validated approach for assessing sample quality and the distribution of non-plasma cell BM populations by MFC could provide a solution. We evaluated BM-associated cell populations, assessed by next-generation flow cytometry (NGF) and white blood cell (WBC) count in 351 BM aspirated samples from 219 participants with plasma cell disorders in the Iceland Screens, Treats, or Prevents MM study (iStopMM), as markers of hemodilution by their discriminatory ability between first and (generally more hemodiluted) second pull BM aspirated samples.

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Background: In 2021, the American College of Medical Genetics and Genomics (ACMG) recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available. Evaluations of the association of actionable genotypes in these genes with life span are currently lacking.

Methods: We assessed the prevalence of coding and splice variants in genes on the ACMG Secondary Findings, version 3.

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Many sequence variants have additive effects on blood lipid levels and, through that, on the risk of coronary artery disease (CAD). We show that variants also have non-additive effects and interact to affect lipid levels as well as affecting variance and correlations. Variance and correlation effects are often signatures of epistasis or gene-environmental interactions.

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Monoclonal gammopathy of undetermined significance (MGUS) is an asymptomatic precursor condition that precedes multiple myeloma and related disorders but has also been associated with other medical conditions. Since systematic screening is not recommended, MGUS is typically diagnosed due to underlying diseases and most cases are not diagnosed. Most previous studies on MGUS disease associations have been based on clinical cohorts, possibly resulting in selection bias.

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Background: Persistent symptoms are common after SARS-CoV-2 infection but correlation with objective measures is unclear.

Methods: We invited all 3098 adults who tested SARS-CoV-2 positive in Iceland before October 2020 to the deCODE Health Study. We compared multiple symptoms and physical measures between 1706 Icelanders with confirmed prior infection (cases) who participated, and 619 contemporary and 13,779 historical controls.

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Smoldering multiple myeloma (SMM) is an asymptomatic precursor to multiple myeloma. Here we define the epidemiological characteristics of SMM in the general population in Iceland. The iStopMM study (ClinicalTrials.

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We report a genome-wide association study of venous thromboembolism (VTE) incorporating 81,190 cases and 1,419,671 controls sampled from six cohorts. We identify 93 risk loci, of which 62 are previously unreported. Many of the identified risk loci are at genes encoding proteins with functions converging on the coagulation cascade or platelet function.

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