Gísli H. Halldórsson
A5001212155- Retinal Imaging and Analysis
- Genetic Associations and Epidemiology
- Glaucoma and retinal disorders
- Optical Imaging and Spectroscopy Techniques
- RNA Research and Splicing
- Cancer-related molecular mechanisms research
- RNA modifications and cancer
- Retinal and Optic Conditions
- Retinal Diseases and Treatments
- Genetic factors in colorectal cancer
- Cancer Genomics and Diagnostics
- Hemoglobinopathies and Related Disorders
- Multiple Myeloma Research and Treatments
- Osteoarthritis Treatment and Mechanisms
- Epigenetics and DNA Methylation
- COVID-19 Clinical Research Studies
- Genomics and Rare Diseases
- Genomic variations and chromosomal abnormalities
- Immunodeficiency and Autoimmune Disorders
- Endometriosis Research and Treatment
- Advanced Proteomics Techniques and Applications
- DNA Repair Mechanisms
- Traumatic Brain Injury and Neurovascular Disturbances
- Medical Image Segmentation Techniques
- SARS-CoV-2 and COVID-19 Research
deCODE Genetics (Iceland)
2016-2025
University of Iceland
2004-2025
Amgen (Germany)
2023
National University Hospital of Iceland
2023
Icelandic Tourism Research Centre
2020
The Icelandic Physiotherapy Association
2009-2018
Genetic diversity arises from recombination and de novo mutation (DNM). Using a combination of microarray genotype whole-genome sequence data on parent-child pairs, we identified 4,531,535 crossover recombinations 200,435 DNMs. The resulting genetic map has resolution 682 base pairs. Crossovers exhibit mutagenic effect, with overrepresentation DNMs within 1 kilobase crossovers in males females. In females, higher rate is observed up to 40 kilobases crossovers, particularly for complex which...
Detailed knowledge of how diversity in the sequence human genome affects phenotypic depends on a comprehensive and reliable characterization both sequences variation. Over past decade, insights into this relationship have been obtained from whole-exome sequencing or whole-genome large cohorts with rich data1,2. Here we describe analysis 150,119 individuals UK Biobank3. This constitutes set high-quality variants, including 585,040,410 single-nucleotide polymorphisms, representing 7.0% all...
High-throughput proteomics platforms measuring thousands of proteins in plasma combined with genomic and phenotypic information have the power to bridge gap between genome diseases. Here we performed association studies Olink Explore 3072 data generated by UK Biobank Pharma Proteomics Project
Nonalcoholic fatty liver (NAFL) and its sequelae are growing health problems. We performed a genome-wide association study of NAFL, cirrhosis hepatocellular carcinoma, integrated the findings with expression proteomic data. For we utilized 9,491 clinical cases proton density fat fraction extracted from 36,116 magnetic resonance images. identified 18 sequence variants associated NAFL 4 cirrhosis, found rare, protective, predicted loss-of-function in MTARC1 GPAM, underscoring them as potential...
Abstract Gene promoter and enhancer sequences are bound by transcription factors depleted of methylated CpG sites (cytosines preceding guanines in DNA). The absence CpGs these typically correlates with increased gene expression, indicating a regulatory role for methylation. We used nanopore sequencing to determine haplotype-specific methylation rates 15.3 million units 7,179 whole-blood genomes. identified 189,178 where three or more proximal were unmethylated on at least one haplotype. A...
To measure hemoglobin oxygen saturation (SO(2)) in retinal vessels and to test the reproducibility sensitivity of an automatic spectrophotometric oximeter.Specialized software automatically identifies blood on fundus images, which are obtained with four different wavelengths light. The calculates optical density ratios (ODRs) for each vessel. was evaluated by analyzing five repeated measurements same vessels. A linear relationship between SO(2) ODR assumed a model derived. After calibration,...
Abstract The great majority of thyroid cancers are the non-medullary type. Here we report findings from a genome-wide association study cancer, including in total 3,001 patients and 287,550 controls five groups European descent. Our results yield novel loci (all with P combined <3 × 10 −8 ): 1q42.2 (rs12129938 PCNXL2 ), 3q26.2 (rs6793295 missense mutation LRCC34 near TERC 5q22.1 (rs73227498 between NREP EPB41L4A 10q24.33 (rs7902587 OBFC1 two independently associated variants at 15q22.33...
Abstract Bone area is one measure of bone size that easily derived from dual-energy X-ray absorptiometry (DXA) scans. In a GWA study DXA the hip and lumbar spine (N ≥ 28,954), we find thirteen independent association signals at twelve loci replicate in samples European East Asian descent ( N = 13,608 – 21,277). Eight associate with osteoarthritis, including rs143384 GDF5 missense variant COL11A1 (rs3753841). The strongest rs11614913[T] microRNA MIR196A2 gene associates P 2.3 × 10 −42 , β...
Objectives To find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) seronegative subsets. Methods We performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) ~1 million controls from Northwestern Europe. searched outside the HLA-locus through effect on coding, mRNA expression in several tissues levels plasma proteins (SomaScan) did network analysis (Qiagen). Results found 25 sequence variants overall, 33 2 RA, altogether...
Back pain is a common and debilitating disorder with largely unknown underlying biology. Here we report genome-wide association study of back using diagnoses assigned in clinical practice; dorsalgia (119,100 cases, 909,847 controls) intervertebral disc (IDD) (58,854 922,958 controls). We identify 41 variants at 33 loci. The most significant (OR
Clonal hematopoiesis (CH) arises when a substantial proportion of mature blood cells is derived from single hematopoietic stem cell lineage. Using whole-genome sequencing 45,510 Icelandic and 130,709 UK Biobank participants combined with mutational barcode method, we identified 16,306 people CH. Prevalence approaches 50% in elderly participants. Smoking demonstrates dosage-dependent impact on risk CH associates several smoking-related diseases. Contrary to published claims, find no evidence...
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 association these life span currently lacking. We assessed prevalence coding splice variants on ACMG Secondary Findings, version 3.0 (ACMG SF v3.0), list genomes 57,933 Icelanders. assigned pathogenicity to all reviewed using reported evidence ClinVar database, frequency...
Abstract Migraine is a complex neurovascular disease with range of severity and symptoms, yet mostly studied as one phenotype in genome-wide association studies (GWAS). Here we combine large GWAS datasets from six European populations to study the main migraine subtypes, aura (MA) without (MO). We identified four new MA-associated variants (in PRRT2 , PALMD ABO LRRK2 ) classified 13 MO-associated variants. Rare effects highlight three genes. A rare frameshift variant brain-expressed confers...
Animal studies have indicated that retinal oxygen consumption is greater in dark than light. In this study, saturation measured vessels of healthy humans during and light.The oximeter consists a fundus camera, beam splitter, digital camera software, which calculates hemoglobin the vessels. first experiment, 18 individuals underwent oximetry measurements after 30 minutes dark, followed by alternating 5-minute periods white light (80 cd/m(2)) dark. second 23 volunteers at 1, 10, 100 cd/m(2)....