-
Expert Review of Endocrinology &... Jul 2024Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive condition. Effective treatment is important as patients are at risk for severe and potentially... (Review)
Review
INTRODUCTION
Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive condition. Effective treatment is important as patients are at risk for severe and potentially fatal acute pancreatitis. We review recent developments in pharmacologic treatment for FCS, namely biological inhibitors of apolipoprotein (apo) C-III and angiopoietin-like protein 3 (ANGPTL3).
AREAS COVERED
FCS follows a biallelic inheritance pattern in which an individual inherits two pathogenic loss-of-function alleles of one of the five causal genes - (in 60-80% of patients), , , , and - leading to the absence of lipolytic activity. Patients present from childhood with severely elevated triglyceride (TG) levels >10 mmol/L. Most patients with severe hypertriglyceridemia do not have FCS. A strict low-fat diet is the current first-line treatment, and existing lipid-lowering therapies are minimally effective in FCS. Apo C-III inhibitors are emerging TG-lowering therapies shown to be efficacious and safe in clinical trials. ANGPTL3 inhibitors, another class of emerging TG-lowering therapies, have been found to require at least partial lipoprotein lipase activity to lower plasma TG in clinical trials. ANGPTL3 inhibitors reduce plasma TG in patients with multifactorial chylomicronemia but not in patients with FCS who completely lack lipoprotein lipase activity.
EXPERT OPINION
Apo C-III inhibitors currently in development are promising treatments for FCS.
Topics: Humans; Hyperlipoproteinemia Type I; Angiopoietin-Like Protein 3; Apolipoprotein C-III; Hypolipidemic Agents; Lipoprotein Lipase; Angiopoietin-like Proteins; Diet, Fat-Restricted; Receptors, Lipoprotein
PubMed: 38866702
DOI: 10.1080/17446651.2024.2365787 -
Nature Genetics Jun 2024Type 2 diabetes (T2D) shows heterogeneous body mass index (BMI) sensitivity. Here, we performed stratification based on BMI to optimize predictions for BMI-related...
Type 2 diabetes (T2D) shows heterogeneous body mass index (BMI) sensitivity. Here, we performed stratification based on BMI to optimize predictions for BMI-related diseases. We obtained BMI-stratified datasets using data from more than 195,000 individuals (n = 55,284) from BioBank Japan (BBJ) and UK Biobank. T2D heritability in the low-BMI group was greater than that in the high-BMI group. Polygenic predictions of T2D toward low-BMI targets had pseudo-R values that were more than 22% higher than BMI-unstratified targets. Polygenic risk scores (PRSs) from low-BMI discovery outperformed PRSs from high BMI, while PRSs from BMI-unstratified discovery performed best. Pathway-specific PRSs demonstrated the biological contributions of pathogenic pathways. Low-BMI T2D cases showed higher rates of neuropathy and retinopathy. Combining BMI stratification and a method integrating cross-population effects, T2D predictions showed greater than 37% improvements over unstratified-matched-population prediction. We replicated findings in the Tohoku Medical Megabank (n = 26,000) and the second BBJ cohort (n = 33,096). Our findings suggest that target stratification based on existing traits can improve the polygenic prediction of heterogeneous diseases.
Topics: Humans; Diabetes Mellitus, Type 2; Multifactorial Inheritance; Body Mass Index; Genetic Predisposition to Disease; Female; Male; Genome-Wide Association Study; Biological Specimen Banks; Middle Aged; Japan; Risk Factors; Aged; Polymorphism, Single Nucleotide; United Kingdom
PubMed: 38862855
DOI: 10.1038/s41588-024-01782-y -
The American Journal of Psychiatry Jul 2024Many but not all persons with bipolar disorder require hospital care because of severe mood episodes. Likewise, some but not all patients experience long-term...
OBJECTIVE
Many but not all persons with bipolar disorder require hospital care because of severe mood episodes. Likewise, some but not all patients experience long-term occupational dysfunction that extends beyond acute mood episodes. It is not known whether these dissimilar outcomes of bipolar disorder are driven by different polygenic profiles. Here, polygenic scores (PGSs) for major psychiatric disorders and educational attainment were assessed for associations with occupational functioning and psychiatric hospital admissions in bipolar disorder.
METHODS
A total of 4,782 patients with bipolar disorder and 2,963 control subjects were genotyped and linked to Swedish national registers. Longitudinal measures from at least 10 years of registry data were used to derive percentage of years without employment, percentage of years with long-term sick leave, and mean number of psychiatric hospital admissions per year. Ordinal regression was used to test associations between outcomes and PGSs for bipolar disorder, schizophrenia, major depressive disorder, attention deficit hyperactivity disorder (ADHD), and educational attainment. Replication analyses of hospital admissions were conducted with data from the Bipolar Disorder Research Network cohort (N=4,219).
RESULTS
Long-term sick leave and unemployment in bipolar disorder were significantly associated with PGSs for schizophrenia, ADHD, major depressive disorder, and educational attainment, but not with the PGS for bipolar disorder. By contrast, the number of hospital admissions per year was associated with higher PGSs for bipolar disorder and schizophrenia, but not with the other PGSs.
CONCLUSIONS
Bipolar disorder severity (indexed by hospital admissions) was associated with a different polygenic profile than long-term occupational dysfunction. These findings have clinical implications, suggesting that mitigating occupational dysfunction requires interventions other than those deployed to prevent mood episodes.
Topics: Humans; Bipolar Disorder; Male; Female; Multifactorial Inheritance; Adult; Sweden; Sick Leave; Middle Aged; Registries; Depressive Disorder, Major; Hospitalization; Educational Status; Unemployment; Schizophrenia; Attention Deficit Disorder with Hyperactivity; Longitudinal Studies; Case-Control Studies
PubMed: 38859703
DOI: 10.1176/appi.ajp.20230073 -
Nature Genetics Jun 2024Genotype × environment interactions (GxE) have long been recognized as a key mechanism underlying human phenotypic variation. Technological developments over the... (Review)
Review
Genotype × environment interactions (GxE) have long been recognized as a key mechanism underlying human phenotypic variation. Technological developments over the past 15 years have dramatically expanded our appreciation of the role of GxE in both gene regulation and complex traits. The richness and complexity of these datasets also required parallel efforts to develop robust and sensitive statistical and computational approaches. Although our understanding of the genetic architecture of molecular and complex traits has been maturing, a large proportion of complex trait heritability remains unexplained. Furthermore, there are increasing efforts to characterize the effect of environmental exposure on human health. We therefore review GxE in human gene regulation and complex traits, advocating for a comprehensive approach that jointly considers genetic and environmental factors in human health and disease.
Topics: Humans; Gene-Environment Interaction; Genotype; Gene Expression Regulation; Multifactorial Inheritance; Phenotype; Quantitative Trait Loci
PubMed: 38858456
DOI: 10.1038/s41588-024-01776-w -
Frontiers in Genetics 2024Infectious hematopoietic necrosis (IHN) is a disease of salmonid fish that is caused by the IHN virus (IHNV), which can cause substantial mortality and economic losses...
Genome-wide association analysis of the resistance to infectious hematopoietic necrosis virus in two rainbow trout aquaculture lines confirms oligogenic architecture with several moderate effect quantitative trait loci.
Infectious hematopoietic necrosis (IHN) is a disease of salmonid fish that is caused by the IHN virus (IHNV), which can cause substantial mortality and economic losses in rainbow trout aquaculture and fisheries enhancement hatchery programs. In a previous study on a commercial rainbow trout breeding line that has undergone selection, we found that genetic resistance to IHNV is controlled by the oligogenic inheritance of several moderate and many small effect quantitative trait loci (QTL). Here we used genome wide association analyses in two different commercial aquaculture lines that were naïve to previous exposure to IHNV to determine whether QTL were shared across lines, and to investigate whether there were major effect loci that were still segregating in the naïve lines. A total of 1,859 and 1,768 offspring from two commercial aquaculture strains were phenotyped for resistance to IHNV and genotyped with the rainbow trout Axiom 57K SNP array. Moderate heritability values (0.15-0.25) were estimated. Two statistical methods were used for genome wide association analyses in the two populations. No major QTL were detected despite the naïve status of the two lines. Further, our analyses confirmed an oligogenic architecture for genetic resistance to IHNV in rainbow trout. Overall, 17 QTL with notable effect (≥1.9% of the additive genetic variance) were detected in at least one of the two rainbow trout lines with at least one of the two statistical methods. Five of those QTL were mapped to overlapping or adjacent chromosomal regions in both lines, suggesting that some loci may be shared across commercial lines. Although some of the loci detected in this GWAS merit further investigation to better understand the biological basis of IHNV disease resistance across populations, the overall genetic architecture of IHNV resistance in the two rainbow trout lines suggests that genomic selection may be a more effective strategy for genetic improvement in this trait.
PubMed: 38854430
DOI: 10.3389/fgene.2024.1394656 -
Psychiatry Research Aug 2024Given that anxiety disorders (AD) are associated with reduced vagally-mediated heart rate variability (HRV), genetic variants related to HRV may provide insight into...
Given that anxiety disorders (AD) are associated with reduced vagally-mediated heart rate variability (HRV), genetic variants related to HRV may provide insight into anxiety etiology. This study used polygenic risk scores (PRS) to explore the genetic overlap between AD and HRV, and investigated whether HRV-related polymorphisms influence anxiety risk. Resting vagally-mediated HRV was measured using a wearable device in 188 European individuals (AD=101, healthy controls=87). AD PRS was tested for association with resting HRV, and HRV PRS for association with AD. We also investigated 15 significant hits from an HRV genome-wide association study (GWAS) for association with resting HRV and AD and if this association is mediated through resting HRV. The AD PRS and HRV PRS showed nominally significant associations with resting HRV and anxiety disorders, respectively. HRV GWAS variants associated with resting HRV were rs12980262 (NDUFA11), rs2680344 (HCN4), rs4262 and rs180238 (GNG11), and rs10842383 (LINC00477). Mediation analyses revealed that NDUFA11 rs12980262 A-carriers and GNG11 rs180238 and rs4262 C-carriers had higher anxiety risk through lower HRV. This study supports an anxiety-HRV genetic relationship, with HRV-related genetic variants translating to AD. This study encourages exploration of HRV genetics to understand mechanisms and identify novel treatment targets for anxiety.
Topics: Humans; Male; Female; Adult; Anxiety Disorders; Heart Rate; Multifactorial Inheritance; Genome-Wide Association Study; Polymorphism, Single Nucleotide; Middle Aged; Young Adult; Biomarkers; Genetic Predisposition to Disease
PubMed: 38850888
DOI: 10.1016/j.psychres.2024.115982 -
BMC Oral Health Jun 2024Individuals born with cleft lip and/or palate who receive corrective surgery regularly have abnormal growth in the midface region such that they exhibit premaxillary...
BACKGROUND
Individuals born with cleft lip and/or palate who receive corrective surgery regularly have abnormal growth in the midface region such that they exhibit premaxillary hypoplasia. However, there are also genetic contributions to craniofacial morphology in the midface region, so although these individuals appear to have Class III skeletal discrepancy, their molar relationship may be Class I. Past genome-wide association studies (GWASs) on skeletal Class II and III malocclusion suggested that multiple genetic markers contribute to these phenotypes via a multifactorial inheritance model, but research has yet to examine the genetic markers associated with dental Class I malocclusion. Thus, our goal was to conduct a family based GWAS to identify genes across the genome that are associated with Class I malocclusion, as defined by molar relations, in humans with and without clefts.
METHODS
Our cohort consisted of 739 individuals from 47 Filipino families originally recruited in 2006 to investigate the genetic basis of orofacial clefts. All individuals supplied blood samples for DNA extraction and genotyping, and a 5,766 single nucleotide polymorphism (SNP) custom panel was used for the analyses. We performed a transmission disequilibrium test for participants with and without clefts to identify genetic contributors potentially involved with Class I malocclusion.
RESULTS
In the total cohort, 13 SNPs had associations that reached the genomic control threshold (p < 0.005), while five SNPs were associated with Class I in the cohort of participants without clefts, including four associations that were identified in the total cohort. The associations for the SNPs ABCA4 rs952499, SOX1-OT rs726455, and RORA rs877228 are of particular interest, as past research found associations between these genes and various craniofacial phenotypes, including cleft lip and/or palate.
CONCLUSIONS
These findings support the multifactorial inheritance model for dental Class I malocclusion and suggest a common genetic basis for different aspects of craniofacial development.
Topics: Humans; Cleft Lip; Cleft Palate; Genome-Wide Association Study; Polymorphism, Single Nucleotide; Female; Male; Malocclusion, Angle Class I; Cohort Studies; Linkage Disequilibrium; Child; Genotype; Adolescent; Genetic Markers; Adult; Phenotype; Multifactorial Inheritance; Young Adult
PubMed: 38849772
DOI: 10.1186/s12903-024-04444-x -
Nature Communications Jun 2024Coronary artery disease (CAD) is the leading cause of death among adults worldwide. Accurate risk stratification can support optimal lifetime prevention. Current methods...
Coronary artery disease (CAD) is the leading cause of death among adults worldwide. Accurate risk stratification can support optimal lifetime prevention. Current methods lack the ability to incorporate new information throughout the life course or to combine innate genetic risk factors with acquired lifetime risk. We designed a general multistate model (MSGene) to estimate age-specific transitions across 10 cardiometabolic states, dependent on clinical covariates and a CAD polygenic risk score. This model is designed to handle longitudinal data over the lifetime to address this unmet need and support clinical decision-making. We analyze longitudinal data from 480,638 UK Biobank participants and compared predicted lifetime risk with the 30-year Framingham risk score. MSGene improves discrimination (C-index 0.71 vs 0.66), age of high-risk detection (C-index 0.73 vs 0.52), and overall prediction (RMSE 1.1% vs 10.9%), in held-out data. We also use MSGene to refine estimates of lifetime absolute risk reduction from statin initiation. Our findings underscore our multistate model's potential public health value for accurate lifetime CAD risk estimation using clinical factors and increasingly available genetics toward earlier more effective prevention.
Topics: Humans; Coronary Artery Disease; Male; Female; Middle Aged; Electronic Health Records; Aged; Risk Assessment; Risk Factors; Adult; Genetic Predisposition to Disease; Hydroxymethylglutaryl-CoA Reductase Inhibitors; United Kingdom; Longitudinal Studies; Multifactorial Inheritance
PubMed: 38849421
DOI: 10.1038/s41467-024-49296-9 -
Scientific Reports Jun 2024Speech-in-noise (SIN) perception is a primary complaint of individuals with audiometric hearing loss. SIN performance varies drastically, even among individuals with...
Speech-in-noise (SIN) perception is a primary complaint of individuals with audiometric hearing loss. SIN performance varies drastically, even among individuals with normal hearing. The present genome-wide association study (GWAS) investigated the genetic basis of SIN deficits in individuals with self-reported normal hearing in quiet situations. GWAS was performed on 279,911 individuals from the UB Biobank cohort, with 58,847 reporting SIN deficits despite reporting normal hearing in quiet. GWAS identified 996 single nucleotide polymorphisms (SNPs), achieving significance (p < 5*10) across four genomic loci. 720 SNPs across 21 loci achieved suggestive significance (p < 10). GWAS signals were enriched in brain tissues, such as the anterior cingulate cortex, dorsolateral prefrontal cortex, entorhinal cortex, frontal cortex, hippocampus, and inferior temporal cortex. Cochlear cell types revealed no significant association with SIN deficits. SIN deficits were associated with various health traits, including neuropsychiatric, sensory, cognitive, metabolic, cardiovascular, and inflammatory conditions. A replication analysis was conducted on 242 healthy young adults. Self-reported speech perception, hearing thresholds (0.25-16 kHz), and distortion product otoacoustic emissions (1-16 kHz) were utilized for the replication analysis. 73 SNPs were replicated with a self-reported speech perception measure. 211 SNPs were replicated with at least one and 66 with at least two audiological measures. 12 SNPs near or within MAPT, GRM3, and HLA-DQA1 were replicated for all audiological measures. The present study highlighted a polygenic architecture underlying SIN deficits in individuals with self-reported normal hearing.
Topics: Humans; Genome-Wide Association Study; Polymorphism, Single Nucleotide; Male; Female; Speech Perception; Multifactorial Inheritance; Adult; Noise; Middle Aged; Self Report; Aged; Hearing; Young Adult
PubMed: 38849415
DOI: 10.1038/s41598-024-63972-2 -
Nature Communications Jun 2024Evidence for adaptation of human skin color to regional ultraviolet radiation suggests shared and distinct genetic variants across populations. However, skin color...
Evidence for adaptation of human skin color to regional ultraviolet radiation suggests shared and distinct genetic variants across populations. However, skin color evolution and genetics in East Asians are understudied. We quantified skin color in 48,433 East Asians using image analysis and identified associated genetic variants and potential causal genes for skin color as well as their polygenic interplay with sun exposure. This genome-wide association study (GWAS) identified 12 known and 11 previously unreported loci and SNP-based heritability was 23-24%. Potential causal genes were determined through the identification of nonsynonymous variants, colocalization with gene expression in skin tissues, and expression levels in melanocytes. Genomic loci associated with pigmentation in East Asians substantially diverged from European populations, and we detected signatures of polygenic adaptation. This large GWAS for objectively quantified skin color in an East Asian population improves understanding of the genetic architecture and polygenic adaptation of skin color and prioritizes potential causal genes.
Topics: Adult; Female; Humans; Male; Middle Aged; Adaptation, Physiological; Chromosome Mapping; Genome-Wide Association Study; Multifactorial Inheritance; Polymorphism, Single Nucleotide; Quantitative Trait Loci; Skin Pigmentation; Ultraviolet Rays; East Asian People
PubMed: 38849341
DOI: 10.1038/s41467-024-49031-4