Genetic Epidemiological Studies Research Articles

The Emerging Potential of Apolipoprotein C-III Inhibition for ASCVD Prevention: A State-of-the-Art Review.

Multiple agents are being developed that inhibit apolipoprotein (apo) C-III. This state-of-the-art review examines their potential for atherosclerotic cardiovascular disease (ASCVD) risk reduction. Apo C-III, an apolipoprotein on the surface of triglyceride-rich lipoproteins (TRLs), impairs clearance of TRLs through both lipoprotein lipase dependent and independent pathways, thereby resulting in increased concentrations of triglycerides. Apo C-III has also been shown to have pro-atherogenic effects when bound to high-density lipoprotein (HDL) particles. Classical and genetic epidemiology studies provide support for the concept that apo C-III is associated with an increased risk of ASCVD events. Drug efficacy of agents that silence APOC3 mRNA has been studied in populations with varying hypertriglyceridemia severity, including those with familial chylomicronemia syndrome, multifactorial chylomicronemia syndrome/severe hypertriglyceridemia, and mixed hyperlipidemia. Randomized controlled trials have reported significant reductions in TG and non-HDL cholesterol levels among these patients treated with APOC3 inhibitors. Upcoming clinical outcomes trials seek to establish a role for APOC3 inhibitors to reduce risk of ASCVD.

Genetic Risk Scores for the Clinical Rheumatologist.

The advent of genome-wide sequencing and large-scale genetic epidemiological studies has led to numerous opportunities for the application of genetics in clinical medicine. Leveraging this information toward the formation of clinically useful tools has been an ongoing research goal in this area. A genetic risk score (GRS) is a measure that attempts to estimate the cumulative contribution of established genetic risk factors toward an outcome of interest, taking into account the cumulative risk that each of these individual genetic risk factors conveys. The purpose of this perspective is to provide a systematic framework to evaluate a GRS for clinical application. Since the initial polygenic risk score methodology in 2007, there has been increasing GRS application across the medical literature. In rheumatology, this has included application to rheumatoid arthritis, gout, spondyloarthritis, lupus, and inflammatory arthritis. GRSs are particularly relevant to rheumatology, where common diseases have many complex genetic factors contributing to risk. Despite this, there is no widely accepted method for the critical application of a GRS, which can be a particular challenge for the clinical rheumatologist seeking to clinically apply GRSs. This review provides a framework by which the clinician may systematically evaluate a GRS. As genotyping becomes more accessible and cost-effective, it will become increasingly important to recognize the clinical applicability of GRSs and identify those of the highest utility for patient care. This framework for the evaluation of a GRS will also help ensure reliability among GRS research in rheumatology, thereby helping to advance the field.

Generation Scotland – Linking all the records we can

ObjectivesGeneration Scotland (GS) is a family-based genetic epidemiology study. Initial recruitment between 2006-11 recruited ~24,000 adults from ~7000 families across Scotland with consent for medical record linkage and re-contact. In 2022 we began recruiting another 20,000, with consent extended to administrative records, with age range now 12+. MethodsOriginal volunteers completed a baseline questionnaire, provided biological samples and underwent clinical assessment. The samples, phenotype and genotype (including methylation) data are linked to routine NHS hospital, maternity, lab test, prescriptions, dentistry, mortality, imaging, cancer screening, GP data records, Covid-19 testing and vaccinations, and follow-up questionnaires. The new wave of recruitment is all online and can be done on a smartphone, with DNA from saliva collected by post. Teenagers aged 12-15 can join with parental consent. ResultsResearchers can find prevalent and incident disease cases and controls, to test research hypotheses on a stratified population. GS is a vanguard cohort testing emerging linkage opportunities in Scotland – including neonatal bloodspots and medical imaging reports. GS has established and validated E-HR linkage with the NHS Scotland CHI Register, overcoming technical and governance issues in the process. We contribute to major international consortia, with collaborators from institutions worldwide, both academic and commercial. ConclusionWe plan to extend the linkage process to include other administrative data from national datasets as and when approvals are obtained. New types of data can also be collected by online questionnaires. The Research Tissue Bank resources are available to academic and commercial researchers through a managed access process.

Generation Scotland Teenage Recruitment – Creating, evaluating and evolving a study sign-up process in collaboration with study participants and young people

ObjectivesGeneration Scotland (GS) is a family-based genetic epidemiology study. Initial recruitment was ~24,000 adult volunteers from across Scotland in 2006-11 with consent for medical record linkage and re-contact. In 2022 we began recruiting another 20,000, with consent extended to administrative records, with age range now 12+. MethodsPeople join the study and complete a questionnaire online, with postal saliva sample collection for DNA. Initially, the consent process required a parent/guardian to join GS, confirm their 12-15 year-old’s capacity for enduring consent and invite their child to join. After launch, parents and young people fed back that the communication and consent methods had a negative effect on the ability of young people to join GS - impacting their autonomy, as they were unable join GS independently of their parents. ResultsThe GS Team designed a new sign-up process for 12–15 year-olds that allowed the teenager to sign up first and request that their parent agree they have capacity to consent. Creating this process was done in collaboration with the new GS YPAG. This new sign-up process was launched in September 2023. We also enabled sign-up using a mobile phone number instead of an email address. ConclusionCo-design of GS recruitment with young people and parents has greatly improved the sign-up process, making GS the first UK longitudinal study where people aged 12-15 can provide enduring consent online with parental confirmation of their capacity. This provides young people with greater ownership over their ability to take part in health research.

Comprehensive Genetic Analysis of Associations between Obesity-Related Parameters and Physical Activity: A Scoping Review.

Genetic epidemiological studies have shown that numerous genetic variants cumulatively increase obesity risk. Although genetically predisposed individuals are more prone to developing obesity, it has been shown that physical activity can modify the genetic predisposition to obesity. Therefore, genetic data obtained from earlier studies, including 30 polymorphisms located in 18 genes, were analyzed using novel methods such as the total genetic score and Biofilter 2.4 software to combine genotypic and phenotypic information for nine obesity-related traits measured before and after the realization of the 12-week training program. The results revealed six genes whose genotypes were most important for post-training changes-LEP, LEPR, ADIPOQ, ADRA2A, ADRB3, and DRD2. Five noteworthy pairwise interactions, LEP × LEPR, ADRB2 × ADRB3, ADRA2A × ADRB3, ADRA2A × ADRB2, ADRA2A × DRD2, and three specific interactions demonstrating significant associations with key parameters crucial for health, total cholesterol (TC), high-density lipoprotein (HDL), and fat-free mass (FFM), were also identified. The molecular basis of training adaptation described in this study would have an enormous impact on the individualization of training programs, which, designed according to a given person's genetic profile, will be effective and safe intervention strategies for preventing obesity and improving health.

Conceptual frameworks for the integration of genetic and social epidemiology in complex diseases

Uncovering the root causes of complex diseases requires complex approaches, yet many studies continue to isolate the effects of genetic and social determinants of disease. Epidemiologic efforts that under-utilize genetic epidemiology methods and findings may lead to incomplete understanding of disease. Meanwhile, genetic epidemiology studies are often conducted without consideration of social and environmental context, limiting the public health impact of genomic discoveries. This divide endures despite shared goals and increases in interdisciplinary data due to a lack of shared theoretical frameworks and differing language. Here, we demonstrate that bridging epidemiological divides does not require entirely new ways of thinking. Existing social epidemiology frameworks including Ecosocial theory and Fundamental Cause Theory, can both be extended to incorporate principles from genetic epidemiology. We show that genetic epidemiology can strengthen, rather than detract from, efforts to understand the impact of social determinants of health. In addition to presenting theoretical synergies, we offer practical examples of how genetics can improve the public health impact of epidemiology studies across the field. Ultimately, we aim to provide a guiding framework for trainees and established epidemiologists to think about diseases and complex systems and foster more fruitful collaboration between genetic and traditional epidemiological disciplines.

Global prevalence of hereditary thrombotic thrombocytopenic purpura determined by genetic analysis

AbstractHereditary thrombotic thrombocytopenic purpura (hTTP) is a rare autosomal recessive, life-threatening disorder caused by a severe deficiency of the plasma enzyme, ADAMTS13. The current estimated prevalence of hTTP in different regions of the world, 0.5 to 2.0 patients per million, is determined by the frequency of diagnosed patients. To evaluate more accurately the worldwide prevalence of hTTP, and also the prevalence within distinct ethnic groups, we used data available in exome and genome sequencing of 807 162 (730 947 exomes, 76 215 genomes) subjects reported recently by the Genome Aggregation Database (gnomAD-v4.1). Among 1 614 324 analyzed alleles in the gnomAD population we identified 6321 distinct ADAMTS13 variants. Of these, 758 were defined as pathogenic; 140 (18%) variants had been previously reported and 618 (82%) were novel (predicted as pathogenic). In total 10 154 alleles (0.6%) were carrying the reported or predicted pathogenic variants; 7759 (77%) with previously reported variants. Considering all 758 pathogenic variants and also only the 140 previously reported variants, we estimated a global hTTP prevalence of 40 and 23 cases per 106, respectively. Considering only the 140 previously reported variants, the highest estimated prevalence was in East Asians (42 per 106). The estimated prevalences of other populations were: Finnish, 32 per 106; non-Finnish Europeans, 28 per 106; Admixed Americans, 19 per 106; Africans/African Americans, 6 per 106; and South Asians, 4 per 106. The lowest prevalences were Middle Eastern, 1 per 106 and Ashkenazi Jews, 0.7 per 106. This population-based genetic epidemiology study reports that hTTP prevalence is substantially higher than the currently estimated prevalence based on diagnosed patients. Many patients with hTTP may not be diagnosed or may have died during the neonatal period.

Anthropometric traits and risk of multiple myeloma: differences by race, sex and diagnostic clinical features

BackgroundObesity is an established modifiable risk factor for multiple myeloma (MM). However, associations of obesity and MM risk in Black populations, for whom obesity and MM are more common, is less clear.MethodsUsing participants enrolled in the Integrative Molecular And Genetic Epidemiology study, we evaluated the association of anthropometric traits with MM risk overall, stratified by race and sex. Among cases, we assessed the association of BMI with the presence of myeloma-defining events.ResultsWe observed an 18% increase in MM risk for every 5 kg/m2 increase in usual adult BMI. Participants with severe obesity (BMI ≥ 40 kg/m2) had the highest risk compared to those with a normal usual adult BMI (18.5–24.9 kg/m2; OR = 1.87, 95% CI 1.25–2.80), particularly among Black men (OR = 3.94, 95% CI 0.90–17.36). Furthermore, MM cases with overweight/obesity (BMI ≥ 25 kg/m2) were more likely to present at diagnosis with low renal function (OR = 1.62, 95% CI 1.09–2.40), deletion 13q (OR = 1.73, 95% CI 1.08–2.76) and lytic lesions or compression fractures (OR = 2.39, 95% CI 0.82–7.01) and less likely to present with severe diffuse osteopenia (OR = 0.51, 95% CI 0.31–0.81).ConclusionsFindings underscore the importance of obesity as a modifiable risk factor for MM, particularly in high-risk populations, and for the clinical presentation of disease.

The genetics of trichotillomania and excoriation disorder: A systematic review

BackgroundTrichotillomania (TTM) and excoriation disorder (ED) are impairing obsessive-compulsive related disorders that are common in the general population and for which there are no clear first-line medications, highlighting the need to better understand the underlying biology of these disorders to inform treatments. Given the importance of genetics in obsessive-compulsive disorder (OCD), evaluating genetic factors underlying TTM and ED may advance knowledge about the pathophysiology of these body-focused repetitive behaviors. AimIn this systematic review, we summarize the available evidence on the genetics of TTM and ED and highlight gaps in the field warranting further research. MethodWe systematically searched Embase, PsycInfo, PubMed, Medline, Scopus, and Web of Science for original studies in genetic epidemiology (family or twin studies) and molecular genetics (candidate gene and genome-wide) published up to June 2023. ResultsOf the 3536 records identified, 109 studies were included in this review. These studies indicated that genetic factors play an important role in the development of TTM and ED, some of which may be shared across the OCD spectrum, but there are no known high-confidence specific genetic risk factors for either TTM or ED. ConclusionsOur review underscores the need for additional genome-wide research conducted on the genetics of TTM and ED, for instance, genome-wide association and whole-genome/whole-exome DNA sequencing studies. Recent advances in genomics have led to the discovery of risk genes in several psychiatric disorders, including related conditions such as OCD, but to date, TTM and ED have remained understudied.

Plasmodium ovale spp dhfr mutations associated with reduced susceptibility to pyrimethamine in sub-Saharan Africa: a retrospective genetic epidemiology and functional study

Mutations in the Plasmodium falciparum dhfr gene confer resistance to pyrimethamine, which is widely used for malaria chemoprevention in Africa. We aimed to evaluate the frequency and evolution of dhfr mutations in Plasmodium ovale spp in Africa and their functional consequences, which are incompletely characterised. We analysed dhfr mutations and their frequencies in P ovale spp isolates collected between Feb 1, 2004, and Aug31, 2023, from the French National Malaria Reference Centre collection and from field studies in Benin, Gabon, and Kenya. Genetic patterns of positive selection were investigated. Full-length recombinant wild-type and mutant DHFR enzymes from both P ovale curtisi and P ovale wallikeri were expressed in bacteria to test whether the most common mutations reduced pyrimethamine susceptibility. We included 518 P ovale spp samples (314 P ovale curtisi and 204 P ovale wallikeri). In P ovale curtisi, Ala15Ser-Ser58Arg was the most common dhfr mutation (39%; 124 of 314 samples). In P ovale wallikeri, dhfr mutations were less frequent, with Phe57Leu-Ser58Arg reaching 17% (34 of 204 samples). These two mutants were the most prevalent in central and east Africa and were fixed in Kenyan isolates. We detected six and four other non-synonymous mutations, representing 8% (24 isolates) and 2% (five isolates) of the P ovale curtisi and Povale wallikeri isolates, respectively. Whole-genome sequencing and microsatellite analyses revealed reduced genetic diversity around themutant pocdhfr and powdhfr genes. The mutant DHFR proteins showed structural changes at the pyrimethamine binding site in-silico, confirmed by a 4-times increase in pyrimethamine half-maximal inhibitory concentration in an Escherichia coli growth assay for the Phe57Leu-Ser58Arg mutant and 50-times increase for the Ala15Ser-Ser58Arg mutant, compared with the wild-type counterparts. The widespread use of sulfadoxine-pyrimethamine for malaria chemoprevention might have exerted fortuitous selection pressure for dhfr mutations in P ovale spp. This calls for closer monitoring of dhfr and dhps mutations in P ovale spp. French Ministry of Health, Agence Nationale de la Recherche, and Global Emerging Infections Surveillance branch of the Armed Forces Health Surveillance Division.

Screening of premature ovarian insufficiency associated genes in Hungarian patients with next generation sequencing

BackgroundPremature ovarian insuffiency (POI) is one of the main cause behind infertility. The genetic analysis of POI should be part of the clinical diagnostics, as several genes have been implicated in the genetic background of it. The aim of our study was to analyse the genetic background of POI in a Hungarian cohort.MethodsThe age of onset was between 15 and 39 years. All patients had the 46,XX karyotype and they were prescreened for the most frequent POI associated FMR1 premutation. To identify genetic alterations next-generation sequencing (NGS) of 31 genes which were previously associated to POI were carried out in 48 unrelated patients from Hungary.ResultsMonogenic defect was identified in 16.7% (8 of 48) and a potential genetic risk factor was found in 29.2% (14 of 48) and susceptible oligogenic effect was described in 12.5% (6 of 48) of women with POI using the customized targeted panel sequencing. The genetic analysis identified 8 heterozygous damaging and 4 potentially damaging variants in POI-associated genes. Further 10 potential genetic risk factors were detected in seven genes, from which EIF2B and GALT were the most frequent. These variants were related to 15 genes: AIRE, ATM, DACH2, DAZL, EIF2B2, EIF2B4, FMR1, GALT, GDF9, HS6ST2, LHCGR, NOBOX, POLG, USP9X and XPNPEP2. In six cases, two or three coexisting damaging mutations and risk variants were identified.ConclusionsPOI is characterized by heterogenous phenotypic features with complex genetic background that contains increasing number of genes. Deleterious variants, which were detected in our cohort, related to gonadal development (oogenesis and folliculogenesis), meiosis and DNA repair, hormonal signaling, immune function, and metabolism which were previously associated with the POI phenotype. This is the first genetic epidemiology study targeting POI associated genes in Hungary. The frequency of variants in different POI associated genes were similar to the literature, except EIF2B and GALT. Both of these genes potential risk factor were detected which could influence the phenotype, although it is unlikely that they can be responsible for the development of the disease by themselves. Advances of sequencing technologies make it possible to aid diagnostics of POI Since individual patients show high phenotypic variance because of the complex network controlling human folliculogenesis. Comprehensive NGS screening by widening the scope to genes which were previously linked to infertility may facilitate more accurate, quicker and cheaper genetic diagnoses for POI. The investigation of patient’s genotype could support clinical decision-making process and pave the way for future clinical trials and therapies.

Ectopical expression of bacterial collagen-like protein supports its role as adhesin in host-parasite coevolution.

For a profound understanding of antagonistic coevolution, it is necessary to identify the coevolving genes. The bacterium Pasteuria and its host, the microcrustacean Daphnia, are a well-characterized paradigm for co-evolution, but the underlying genes remain largely unknown. A genome-wide association study suggested a Pasteuria collagen-like protein 7 (Pcl7) as a candidate mediating parasite attachment and driving its coevolution with the host. Since Pasteuria ramosa cannot currently be genetically manipulated, we used Bacillus thuringiensis to express a fusion protein of a Pcl7 carboxy-terminus from P. ramosa and the amino-terminal domain of a B. thuringiensis collagen-like protein (CLP). Mutant B. thuringiensis (Pcl7-Bt) spores but not wild-type B. thuringiensis (WT-Bt) spores attached to the same site of susceptible hosts as P. ramosa. Furthermore, Pcl7-Bt spores attached readily to susceptible host genotypes, but only slightly to resistant host genotypes. These findings indicated that the fusion protein was properly expressed and folded and demonstrated that indeed the C-terminus of Pcl7 mediates attachment in a host genotype-specific manner. These results provide strong evidence for the involvement of a CLP in the coevolution of Daphnia and P. ramosa and open new avenues for genetic epidemiological studies of host-parasite interactions.

Abstract 921: The value of cancer genomic data sharing

Abstract Our understanding of and ability to combat cancer relies on the generation, analysis, and sharing of data. The Epidemiology and Genomics Research Program in the National Cancer Institute’s Division of Cancer Control and Population Sciences (DCCPS) has supported generation of large genomic data sets and advocated for and/or required broad sharing of this data. One of DCCPS’s scientific priorities is focused on data strategies namely, “the use, enhancement, expansion, and accessibility of new and existing DCCPS-supported data resources to accelerate cancer control research” (https://cancercontrol.cancer.gov/overview-highlights/2022/future_directions.html).EGRP funded the Genetic Associations and Mechanisms in Oncology (GAME-ON) Initiative, a multidisciplinary collaboration of researchers focused on understanding the genetic architecture, biology, and clinical and epidemiologic utility of common cancer risk variants. This program focused on 5 common cancer types - breast, colorectal, lung, ovarian, and prostate - and required research that incorporated multiple research domains and sharing of any data generated. A major accomplishment of this program was development of the OncoArray genotyping chip, which used information from genetic epidemiology studies, biological/functional analyses, and clinical and epidemiologic insights to create a comprehensive, high-density genotyping array for pan-cancer studies that has led to the discovery of hundreds of new cancer predisposition variants. This chip was used in a massive, coordinated genotyping effort that culminated in the generation of 7 datasets comprising genotyping data for nearly 500,000 individuals. All the data were deposited in dbGaP between 2014 and 2021 and are available (via controlled access) to any investigators. To understand the secondary use of these data, we determined the number of times the data had been downloaded, who downloaded the data, and types of research for which it was used. We also identified publications using OncoArray data and characterized the publications by research type, cancer type, and other details. Through this analysis, we explore how well the GAME-ON initiative and the OncoArray projects promote the DCCPS scientific priority of optimizing secondary research by making the data findable, accessible, interoperable, and reusable (FAIR). Citation Format: Stefanie Nelson, Charlisse Caga Anan, Elizabeth Gillanders. The value of cancer genomic data sharing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 921.

Abstract 848: Influence of young age at diagnosis on the clinical presentation of disease and survival among patients with multiple myeloma

Abstract Background: Age is an important prognostic factor for multiple myeloma (MM). We evaluated the influence of age on the clinical presentation and outcomes among newly diagnosed patients with MM to optimize risk stratification. Methods: In 850 patients with first primary confirmed MM prospectively enrolled in the Integrative Molecular And Genetic Epidemiology (IMAGE) study (2009-2020), we evaluated the presence of diagnostic myeloma-defining events (MDE), progression free survival (PFS) and overall survival (OS) by young age at diagnosis (≤50 years). We evaluated the association of young age with the prevalence of diagnostic MDE, clinical features and chromosomal abnormalities using the prevalence odds ratio (OR) and corresponding 95% confidence interval (CI) calculated from multivariable logistic regression. Median PFS and OS were graphically examined using Kaplan-Meier survival curves with log-rank tests used to compare survival by diagnostic age group. Risks of disease progression and all-cause mortality were estimated using hazard ratios (HR) and corresponding 95% CI calculated from multivariable Cox proportional hazard models. Results.: Of the 850 patients, 15.4% were diagnosed at ≤50 years of age, 54% were male and 40% self-identified as Black. Compared to patients diagnosed with MM over the age of 50, young patients were more likely to self-identify as Black (59.5% vs 40.5%; P<0.0001) and to report a negative smoking history (66.2% v 56.4%; P=0.01), and less likely to present with age-dependent comorbidities including hypertension, hyperlipidemia and diabetes mellitus type II (P≤0.0001). In multivariable analyses, young patients, compared to older patients, were more likely to present at diagnosis with higher median percent bone marrow plasma cells (70% v 55%; P=0.02) and to undergo autologous stem cell transplant (ASCT) as part of their first-line treatment (82.0% v 67.6%; P=0.01) after controlling for sex, race, body mass index, smoking status and comorbidities. We did not observe significant associations of young age with the prevalence of any other MDE, clinical feature or chromosomal abnormality evaluated. The median OS was 106.9 months (range, 0.23-356.1). OS was significantly longer in young patients with MM compared to patients aged greater than 50 years (159 v 99 months, respectively; P<0.001) leading to a suggestive 1.5-fold decreased risk of mortality among younger newly diagnosed patients (HR=0.67, 95% CI 0.39-1.14; P=0.14) after adjusting for sex, International Staging System-stage, adverse cytogenetic abnormalities, and ASCT. We did not observe associations with age and PFS (P=0.81). Conclusions: Findings suggest that newly diagnosed younger patients with MM are more likely to self-identify as Black, present with more bone marrow plasma cells, have less age-dependent comorbidities, and undergo ASCT leading to a suggestive survival advantage. Citation Format: Krystle L. Ong, Kevin D. Arnold, Gayathri Ravi, Luciano J. Costa, Elizabeth E. Brown. Influence of young age at diagnosis on the clinical presentation of disease and survival among patients with multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 848.

Genetics of chronic respiratory disease.

Chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD), asthma and interstitial lung diseases are frequently occurring disorders with a polygenic basis that account for a large global burden of morbidity and mortality. Recent large-scale genetic epidemiology studies have identified associations between genetic variation and individual respiratory diseases and linked specific genetic variants to quantitative traits related to lung function. These associations have improved our understanding of the genetic basis and mechanisms underlying common lung diseases. Moreover, examining the overlap between genetic associations of different respiratory conditions, along with evidence for gene-environment interactions, has yielded additional biological insights into affected molecular pathways. This genetic information could inform the assessment of respiratory disease risk and contribute to stratified treatment approaches.

Sleep and allergic diseases among young Chinese adults from the Singapore/Malaysia Cross-Sectional Genetic Epidemiology Study (SMCGES) cohort

Background and objectiveSleep disruption has been shown to affect immune function and thus influence allergic disease manifestation. The specific effects of sleep on allergic diseases, however, are less well-established; hence, in a unique population of young Chinese adults, we investigated the association between sleep and allergic disease.MethodsYoung Chinese adults recruited from Singapore in the Singapore/Malaysia Cross-Sectional Genetic Epidemiology Study (SMCGES) were analyzed. We used the International Study of Asthma and Allergies in Childhood (ISAAC) protocol and a skin prick test to determine atopic dermatitis (AD), allergic rhinitis (AR), and asthma status. Information regarding total sleep time (TST) and sleep quality (SQ) was also obtained.ResultsOf 1558 participants with a mean age of 25.0 years (SD = 7.6), 61.4% were female, and the mean total sleep time (TST) was 6.8 h (SD = 1.1). The proportions of AD, AR, and asthma were 24.5% (393/1542), 36.4% (987/1551), and 14.7% (227/1547), respectively. 59.8% (235/393) of AD cases suffered from AD-related sleep disturbances, 37.1% (209/564) of AR cases suffered from AR-related sleep disturbances, and 25.1% (57/227) of asthma cases suffered from asthma-related sleep disturbances. Only asthma cases showed a significantly lower mean TST than those without asthma (p = 0.015). Longer TST was significantly associated with lower odds of AR (OR = 0.905, 95% CI = 0.820–0.999) and asthma (OR = 0.852, 95% CI = 0.746–0.972). Linear regression analyses showed that lower TST was significantly associated with asthma (β = − 0.18, SE = 0.076, p-value = 0.017), and AR when adjusted for AR-related sleep disturbances (β = − 0.157, SE = 0.065, p-value = 0.016). Only sleep disturbances due to AR were significantly associated with a poorer SQ (OR = 1.962, 95% CI = 1.245–3.089).ConclusionsWe found that sleep quality, but not sleep duration was significantly poorer among AD cases, although the exact direction of influence could not be determined. In consideration of the literature coupled with our findings, we posit that TST influences allergic rhinitis rather than vice versa. Finally, the association between TST and asthma is likely mediated by asthma-related sleep disturbances, since mean TST was significantly lower among those with nighttime asthma symptoms. Future studies could consider using objective sleep measurements coupled with differential expression analysis to investigate the pathophysiology of sleep and allergic diseases.

Lung Cancer in Ever- and Never-Smokers: Findings from Multi-Population GWAS Studies.

Clinical, molecular, and genetic epidemiology studies displayed remarkable differences between ever- and never-smoking lung cancer. We conducted a stratified multi-population (European, East Asian, and African descent) association study on 44,823 ever-smokers and 20,074 never-smokers to identify novel variants that were missed in the non-stratified analysis. Functional analysis including expression quantitative trait loci (eQTL) colocalization and DNA damage assays, and annotation studies were conducted to evaluate the functional roles of the variants. We further evaluated the impact of smoking quantity on lung cancer risk for the variants associated with ever-smoking lung cancer. Five novel independent loci, GABRA4, intergenic region 12q24.33, LRRC4C, LINC01088, and LCNL1 were identified with the association at two or three populations (P < 5 × 10-8). Further functional analysis provided multiple lines of evidence suggesting the variants affect lung cancer risk through excessive DNA damage (GABRA4) or cis-regulation of gene expression (LCNL1). The risk of variants from 12 independent regions, including the well-known CHRNA5, associated with ever-smoking lung cancer was evaluated for never-smokers, light-smokers (packyear ≤ 20), and moderate-to-heavy-smokers (packyear > 20). Different risk patterns were observed for the variants among the different groups by smoking behavior. We identified novel variants associated with lung cancer in only ever- or never-smoking groups that were missed by prior main-effect association studies. Our study highlights the genetic heterogeneity between ever- and never-smoking lung cancer and provides etiologic insights into the complicated genetic architecture of this deadly cancer.

Genetically determined plasma trefoil factor-3 levels are causally associated with the risk of ulcerative colitis: a Mendelian randomization study

Objectives: Ulcerative colitis (UC) is an inflammatory disease restricted to the colon's mucosal layer. UC is a complex disease with a largely unknown etiology. Mendelian Randomization (MR) is a method that uses variations in genes that have a causal effect of a modifiable exposure to the disease, in genetic epidemiological studies. Trefoil factor 3 (TFF3) is a secreted protein expressed mainly in the colonic mucosa that binds with the mucin 2 protein, forming a protective barrier for the colon mucosa from bacteria and other insults. This study aimed to identify if TFF3 levels in plasma are causally associated with UC. Methods: We performed a two-sample MR study. For exposure instrumental variables (IVs), genetically determined TFF3 levels in plasma proteome quantitative trait locus data were obtained from the published literature. Outcome data were obtained from the GWAS catalog. The “TwoSampleMR” R package was used for MR. The statistical significance of IV effect sizes on the outcome is mainly evaluated by the inverse variance weighted (IVW) method. Results: The IVW test showed considerable statistical significance in all analyzed outcomes except for Crohn’s disease (CD) samples. Heterogeneity and horizontal pleiotropy tests showed no significant results for MR sensitivity analysis. Conclusions: We showed that TFF3 levels in plasma were causally associated with the risk of UC. Increased levels of TFF3 are reversely associated with the risk of UC. The absence of any causal relationship between TFF3 and CD from the same study cohort also supports our causal inference.

Bioinformatics analysis to identify the relationship between human papillomavirus-associated cervical cancer, toll-like receptors and exomes: A genetic epidemiology study.

Genetic variants may influence Toll-like receptor (TLR) signaling in the immune response to human papillomavirus (HPV) infection and lead to cervical cancer. In this study, we investigated the pattern of TLR expression in the transcriptome of HPV-positive and HPV-negative cervical cancer samples and looked for variants potentially related to TLR gene alterations in exomes from different populations. A cervical tissue sample from 28 women, which was obtained from the Gene Expression Omnibus database, was used to examine TLR gene expression. Subsequently, the transcripts related to the TLRs that showed significant gene expression were queried in the Genome Aggregation Database to search for variants in more than 5,728 exomes from different ethnicities. Cancer and HPV were found to be associated (p<0.0001). TLR1(p = 0.001), TLR3(p = 0.004), TLR4(221060_s_at)(p = 0.001), TLR7(p = 0.001;p = 0.047), TLR8(p = 0.002) and TLR10(p = 0.008) were negatively regulated, while TLR4(1552798_at)(p<0.0001) and TLR6(p = 0.019) were positively regulated in HPV-positive patients (p<0.05). The clinical significance of the variants was statistically significant for TLR1, TLR3, TLR6 and TLR8 in association with ethnicity. Genetic variants in different TLRs have been found in various ethnic populations. Variants of the TLR gene were of the following types: TLR1(5_prime_UTR), TLR4(start_lost), TLR8(synonymous;missense) and TLR10(3_prime_UTR). The "missense" variant was found to have a risk of its clinical significance being pathogenic in South Asian populations (OR = 56,820[95%CI:40,206,80,299]). The results of this study suggest that the variants found in the transcriptomes of different populations may lead to impairment of the functional aspect of TLRs that show significant gene expression in cervical cancer samples caused by HPV.

BIODEMOGRAPHY OF AGING, CELEBRATING JAMES W. VAUPEL, PHD

Abstract James W. Vaupel, PhD (1945 – 2022), was an international leader in demography and aging research and a pioneer in the field of biodemography. He was a highly creative researcher and very entrepreneurial in the development of new interdisciplinary research environments. This symposium highlights a few of the biodemographic research areas that Dr. Vaupel has been a catalyst for. Denmark was Dr. Vaupel’s home country during the last third of his life, and Dr. Christensen reports on findings from Danish nationwide genetic-epidemiological studies on twins and the oldest old: familial influence on aging phenotypes, cohort differences in health among the oldest old, associations of early life events with late life health, as well as tongue-in-cheek research on perceived age and teeth. Dr. Alberts discusses the ‘invariant rate of aging’ hypothesis that was developed by Vaupel and others. She presents comparative analyses from multiple nonhuman primate populations showing that, while life expectancy can continue to improve, we probably can’t slow the demographic rate of aging. Dr. Campos presents evidence from a wild baboon population in Kenya that glucocorticoid levels—biological markers of stress responses—are strong prognostic indicators of survival and may be key explanations of life span disparities. Dr. Carey presents key discoveries from large-scale studies involving the Mediterranean fruit fly. These include the slowing of mortality at older ages, context-specific sex mortality differentials, a behavioral biomarker for morbidity, dietary conditions for maximizing lifespan versus reproduction and a stationary population identity whereby life lived equals life left.