LocusZoom: regional visualization of genome-wide association scan results

Human genetic variation reveals FCRL3 is a lymphocyte receptor for Yersinia pestis

Yersinia pestis is the bacterium responsible for plague, one of the deadliest diseases in history. To discover human genetic determinants of Y. pestis infection, we utilized nearly 1,000 genetically diverse lymphoblastoid cell lines in a cellular genome-wide association study. A nonsynonymous SNP, rs2282284 (N721S), in Fc receptor-like 3 (FCRL3) was associated with bacterial invasion of host cells (p = 9 × 10-8). Overexpressed FCRL3 facilitated attachment and invasion of Y. pestis and colocalized with Y. pestis at attachment sites. These properties were variably conserved across the FCRL family, revealing an immunoglobulin-like domain and signaling motifs shared by FCRL3 and FCRL5 to be necessary for attachment and invasion. Direct binding to FCRL5 extracellular domain was confirmed, and B cells (the primary cells that express FCRLs) were preferentially invaded by Y. pestis. Thus, Y. pestis hijacks FCRL proteins, possibly taking advantage of an immune receptor to create a lymphocyte niche during infection.

A genome-wide association study identifies novel genetic variants associated with neck or shoulder pain in the UK biobank (N = 430,193)

Introduction

Neck and shoulder pain are prevalent musculoskeletal disorders that significantly affect the quality of life for a substantial portion of the global population. Studies have shown that women are more susceptible than men.

Objective

This study aims to discover genetic variants associated with neck or shoulder pain through a genome-wide association study (GWAS), using data from 430,193 participants in the UK Biobank.

Methods

A genome-wide association study was performed adjusting for age, sex, BMI, and 8 population principal components. Significant and independent genetic variants were replicated by FinnGen.

Results

The primary GWAS revealed 5 significant genetic loci (including 2 novel) associated with neck or shoulder pain, with the most significant single nucleotide polymorphism (SNP) being rs9889282 (P = 2.63 × 10-12) near CA10 on chromosome 17. Two novel significant associations were detected on chromosomes 18 and 14, with the top SNPs being rs4608411 (P = 8.20 × 10-9) near TCF4 and rs370565192 (P = 3.80 × 10-8) in DCAF5, respectively. Our secondary GWAS identified a single novel genetic locus in SLC24A3 among males and 2 genetic loci (including one novel near LINC02770) among females. In the replication stage, the SLC39A8 locus was weakly supported by the FinnGen cohort. The tissue expression analysis revealed a significant association between brain tissues and neck or shoulder pain.

Conclusion

In summary, this study has identified novel genetic variants for neck or shoulder pain. Sex-stratified GWAS also suggested that sex played a role in the occurrence of the phenotype.

Genetic variants of FER and SULF1 in the fibroblast-related genes are associated with non-small-cell lung cancer survival

Fibroblasts are important components in the tumor microenvironment and can affect tumor progression and metastasis. However, the roles of genetic variants of the fibroblast-related genes (FRGs) in the prognosis of non-small-cell lung cancer (NSCLC) patients have not been reported. Therefore, we investigated the associations between 26,544 single nucleotide polymorphisms (SNPs) in 291 FRGs and survival of NSCLC patients from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. In Cox regression multivariable analysis, we found that 661 SNPs were associated with NSCLC overall survival (OS). Then we validated these SNPs in another independent replication dataset of 984 patients from the Harvard Lung Cancer Susceptibility (HLCS) Study. Finally, we identified two independent SNPs (i.e., FER rs7716388 A>G and SULF1 rs11785839 G>C) that remained significantly associated with NSCLC survival with hazards ratios (HRs) of 0.87 (95% confidence interval [CI] = 0.77-0.98, p = 0.018) and 0.88 (95% CI = 0.79-0.99, p = 0.033), respectively. Combined analysis for these two SNPs showed that the number of protective alleles was associated with better OS and disease-specific survival. Expression quantitative trait loci analysis indicated that the FER rs7716388 G allele was associated with the up-regulation of FER mRNA expression levels in lung tissue. Our results indicated that these two functional SNPs in the FRGs may be prognostic biomarkers for the prognosis of NSCLC patients, and the possible mechanism may be through modulating the expression of their corresponding genes.

Distinct genetic risk loci between biopsy-proven renal and non-renal lupus: a 10-year longitudinal cohort

OBJECTIVE

Systemic lupus erythematosus (SLE) is a heterogeneous disease that manifests as different subphenotypes. Distinct subphenotypes, such as lupus nephritis (LN), have been associated with increased genetic risk, but prior studies have been limited by cross-sectional and imprecisely subphenotyped cohorts. This study investigated the genetic basis for LN using a longitudinal cohort of distinctly subphenotyped patients.

METHODS

SLE patients with biopsy-proven LN or never developed LN (NLN) were recruited from eight tertiary referral centres. All patients had longitudinal clinical data for at least 10 years, or died during the study period. NLN patients had no renal involvement for at least 10 years. Subjects were genotyped and polygenic risk scores (PRS) were calculated using 230 SLE-associated SNPs. Genome-wide association analyses were also conducted for LN vs control, NLN vs control, and LN vs NLN comparisons, along with heterogeneity tests to assess differences in effect size.

RESULTS

Among 1462 patients, 824 (56%) and 638 (44%) had LN and NLN, respectively. PRS was significantly higher in the LN cohort. Genome-wide significant variants were identified in HLA, TNFAIP3, BLK and STAT4 loci specifically for LN patients, while STAT4 also remained significant for NLN patients. Direct LN vs NLN associations showed no statistically significant variants but heterogeneity tests revealed other genetic loci, including ELF1, OX40, DUSP22 and TPCN2.

CONCLUSION

Different subphenotypes of SLE are predisposed by distinct genetic risk loci, which can only be identified in clearly subphenotyped cohorts with sufficient longitudinal data. We identified unique genetic risk loci enriched among patients with biopsy-proven LN, and postulate that individual subphenotypes may have varying genetic predisposition.

The GWAS candidate far upstream element binding protein 3 (FUBP3) is required for normal skeletal growth, and adult bone mass and strength in mice

Bone mineral density (BMD) and height are highly heritable traits for which hundreds of genetic loci have been linked through genome wide association studies (GWAS). FUBP3 is a DNA and RNA binding protein best characterised as a transcriptional regulator of c-Myc, but little is known about its role in vivo. Single nucleotide polymorphisms in FUBP3 at the 9q34.11 locus have been associated with BMD, fracture and height in multiple GWAS, but FUBP3 has no previously established role in the skeleton. We analysed Fubp3-deficient mice to determine the consequence of FUBP3 deficiency in vivo. Mice lacking Fubp3 had reduced survival to adulthood and impaired skeletal growth. Bone mass was decreased, most strikingly in the vertebrae, with altered trabecular micro-architecture. Fubp3 deficient bones were also weak. These data provide the first functional demonstration that Fubp3 is required for normal skeletal growth and development and maintenance of adult bone structure and strength, indicating that FUBP3 contributes to the GWAS association of 9q34.11 with variation in height, BMD and fracture.

Genome-Wide Association Study on Muscle Stiffness Identified Novel Locus for Predisposition to Muscle Strain Injury

PURPOSE

We aimed to screen the entire genome for genetic variants associated with passive muscle stiffness, which has been suggested as a risk factor for muscle strain injury.

METHODS

This genome-wide association study (GWAS) on passive muscle stiffness included 350 physically active young Japanese individuals. Three hamstring constituents were measured using ultrasound shear wave elastography. Skeletal muscle transcriptomes were compared across the genotypes of GWAS-identified variants in 48 healthy Japanese individuals. Association between GWAS-identified variants and history of muscle strain injury was examined in 1428 Japanese athletes.

RESULTS

Two loci on chromosome 11 demonstrated a genome-wide significant association with passive muscle stiffness of the biceps femoris long head (rs12807854 T/C: P = 5.19 × 10 -10 , rs78405694 T/C: P = 2.09 × 10 -8 ; linear regression analysis adjusted for sex, age, and stretching exercise habits). Skeletal muscle RNA sequencing revealed significantly elevated expression of extracellular matrix-related genes in muscles carrying stiffness-increasing alleles of these variants. Among athletes, rs12807854 T/C was significantly associated with a history of muscle strain injury ( P = 0.0254; logistic regression analysis adjusted for age, sex, competitive level, and main sport). Carriers of the C allele, associated with increased muscle stiffness, exhibited a heightened risk of muscle strain injury (odds ratio = 1.62; 95% confidence interval = 1.06-2.47 per C allele increase). By contrast, rs78405694 did not show a significant association with muscle strain injury in this population.

CONCLUSIONS

A novel locus associated with passive muscle stiffness and muscle strain injury was identified. Elucidating the detailed mechanisms linking the identified locus to passive muscle stiffness may lead to the development of new strategies to prevent muscle strain injuries.

Genome-wide association studies in a large Korean cohort identify quantitative trait loci for 36 traits and illuminate their genetic architectures

Genome-wide association studies (GWAS) have predominantly focused on European ancestry populations, limiting biological discoveries across diverse populations. Here we report GWAS findings from 153,950 individuals across 36 quantitative traits in the Korean Cancer Prevention Study-II (KCPS2) Biobank. We discovered 301 previously unreported genetic loci in KCPS2, including an association between thyroid-stimulating hormone and CD36. Meta-analysis with the Korean Genome and Epidemiology Study, Biobank Japan, Taiwan Biobank, and UK Biobank identified 4588 loci that were not significant in any contributing GWAS. We describe differences in genetic architectures across these East Asian and European samples. We also highlight East Asian specific associations, including a known pleiotropic missense variant in ALDH2, which fine-mapping identified as a likely causal variant for multiple traits. Our findings provide insights into the genetic architecture of complex traits in East Asian populations and highlight how broadening the population diversity of GWAS samples can aid discovery.

Genome-wide association study identified novel loci and gene-environment interaction for refractive error in children

To identify novel genetic loci for children refractive error, we performed a meta-analysis of two genome-wide association studies (GWASs) of spherical equivalent (SE) in 1,237 children from the population-based Hong Kong Children Eye Study (HKCES) and the Low Concentration Atropine for Myopia Progression (LAMP) study. Replication was conducted in 4,093 Chinese children and 1,814 Chinese adults. Four lead-SNPs (MIR4275 rs292034, TENM3 rs17074027, LOC101928911 rs6925312 and FAM135B rs4609227) showed genome-wide significant association (P ≤ 5.0 × 10-8) with SE. TENM3 had been associated with myopia in adults before, whilst the other three loci, MIR4275, LOC101928911 and FAM135B, were novel. Significant interaction between genetic risk scores (GRS) and near work on SE was also detected (βinteraction = 0.14, Pinteraction = 0.0003). This study identified novel genetic loci for children refractive error and suggested myopia intervention can be individualized based on the genetic risk of children.

Genome-Wide Association Study of Age-Related Hearing Loss in CFW Mice Identifies Multiple Genes and Loci, Including Prkag2

PURPOSE

Age-related hearing loss (ARHL) is one of the most prevalent conditions affecting the elderly. ARHL is influenced by a combination of environmental and genetic factors; the identification of the genes that confer risk will aid in the prevention and treatment of ARHL. The mouse and human inner ears are functionally and genetically homologous. We used Carworth Farms White (CFW) mice to study the genetic basis of ARHL because they are genetically diverse and exhibit variability in the age of onset and severity of ARHL.

METHODS

Hearing at a range of frequencies was measured using auditory brainstem response (ABR) thresholds in 946 male and female CFW mice at the age of 1, 6, and 10 months. We genotyped the mice using low-coverage (mean coverage 0.27 ×) whole-genome sequencing (lcWGS) followed by imputation using STITCH. To determine the accuracy of the genotypes, we sequenced 8 samples at > 30 × coverage and used those data to estimate the accuracy of lcWGS genotyping, which was > 99.5%. We performed a genome-wide association study (GWAS) for the ABR thresholds for each frequency at each age, and we also performed a GWAS for age at deafness.

RESULTS

We obtained genotypes at 4.18 million single nucleotide polymorphisms (SNP). The SNP heritability for traits ranged from 0 to 42%. GWAS identified 10 significant associations with ARHL that contained potential candidate genes, including Dnah11, Rapgef5, Cpne4, Prkag2, and Nek11. Genetic ablation of Prkag2 caused ARHL at high frequencies, strongly suggesting that Prkag2 is the causal gene for one of the associations.

CONCLUSIONS

GWAS for ARHL in CFW outbred mice identified genetic risk factors for ARHL, including Prkag2. Our results will help to define novel therapeutic targets for the treatment and prevention of this common disorder.

Mapping chromatin interactions at melanoma susceptibility loci uncovers distant cis-regulatory gene targets

Genome-wide association studies (GWASs) of melanoma risk have identified 68 independent signals at 54 loci. For most loci, specific functional variants and their respective target genes remain to be established. Capture-HiC is an assay that links fine-mapped risk variants to candidate target genes by comprehensively mapping chromatin interactions. We performed a melanoma GWAS region-focused capture-HiC assay in human primary melanocytes to identify physical interactions between fine-mapped risk variants and potential causal melanoma-susceptibility genes. Overall, chromatin-interaction data alone nominated potential causal genes for 61 of the 68 melanoma risk signals, identifying many candidates beyond those reported by previous studies. We further integrated these data with epigenomic (chromatin state, accessibility), gene expression (expression quantitative trait locus [eQTL]/transcriptome-wide association study [TWAS]), DNA methylation (methylation QTL [meQTL]/methylome-wide association study [MWAS]), and massively parallel reporter assay (MPRA) data generated from melanoma-relevant cell types to prioritize potentially cis-regulatory variants and their respective candidate gene targets. From the set of fine-mapped variants across these loci, we identified 140 prioritized credible causal variants linked to 195 candidate genes at 42 risk signals. In addition, we developed an integrative scoring system to facilitate candidate gene prioritization, integrating melanocyte and melanoma datasets. Notably, at several GWAS risk signals, we observed long-range chromatin connections (500 kb to >1 Mb) with distant candidate target genes. We validated several such cis-regulatory interactions using CRISPR inhibition, providing evidence for known cancer driver genes MDM4 and CBL, as well as the SRY-box transcription factor SOX4, as likely melanoma risk genes.

Systematic review and independent validation of genetic factors of radiographic outcome in rheumatoid arthritis identifies a genome-wide association with CARD9

OBJECTIVES

This study aimed to investigate non-HLA genetic mechanisms underlying radiographic severity in rheumatoid arthritis (RA).

METHODS

A systematic review of publications reporting non-HLA genetic associations with radiographic severity in RA across ancestries was undertaken. Experimental validation was performed in the Norfolk Arthritis Register, comprising 1407 patients with available genetic and treatment data followed prospectively for up to 10 years, with 2198 longitudinal radiographs. Genome-wide genotyping was performed with Illumina Human Core Exome Array. Radiographic outcomes (presence of erosions; Larsen score) were modelled longitudinally. Fine mapping and functional annotations to refine associations to potential causative loci were undertaken using FUMA, PolyPhen2, and RegulomeDB.

RESULTS

The systematic review identified 102 publications reporting 139 independent associations with radiographic outcome. Association with 15 independent polymorphisms were replicated in the Norfolk Arthritis Register data set, implicating adaptive immune processes (Th1, Th2, and Th17 pathways), cytokine regulation, and osteoclast differentiation. Notably, we refined the association of rs59902911 at the CARD9 locus to an intronic polymorphism within an active enhancer (rs78892335), achieving genome-wide significance and with an effect size exceeding the minimal clinically important difference for each copy of the minor allele (4.78 Larsen units/copy; 95% CI, 3.15-6.41; p = 9.01 × 10-9). This polymorphism is associated with the expression of CARD9 in immune cells, including B cells.

CONCLUSIONS

We provide a comprehensive list of validated genetic associations with RA outcome and demonstrate that non-HLA polymorphisms can associate with radiographic severity independently of disease susceptibility. This highlights the importance of dedicated genetic outcome studies for patient stratification in precision medicine for RA.

DCC in the cerebral cortex is required for cognitive functions in mouse

Schizophrenia (SZ) is a highly heritable mental disorder, and genome-wide association studies have identified the association between deleted in colorectal cancer (DCC) and SZ. Previous study has shown a lowered expression of DCC in the cerebral cortex of SZ patient. In this study, we identified novel single nucleotide polymorphisms (SNPs) of DCC statistically correlated with SZ. Based on these, we generated DCC conditional knockout (CKO) mice and explored behavioral phenotypes in these mice. We observed that deletion of DCC in cortical layer VI but not layer V led to deficits in fear and spatial memory, as well as defective sensorimotor gating revealed by the prepulse inhibition test (PPI). Critically, the defective sensorimotor gating could be restored by olanzapine, an antipsychotic drug. Furthermore, we found that the levels of p-AKT and p-GSK3α/β were decreased, which was responsible for impaired PPI in the DCC-deficient mice. Finally, the DCC-deficient mice also displayed reduced spine density of pyramidal neurons and disturbed delta-oscillations. Our data, for the first time, identified and explored downstream substrates and signaling pathway of DCC which supports the hypothesis that DCC is a SZ-related risky gene and when defective, may promote SZ-like pathogenesis and behavioral phenotypes in mice.

A non-syndromic orofacial cleft risk locus links tRNA splicing defects to neural crest cell pathologies

Orofacial clefts are the most common form of congenital craniofacial malformation worldwide. The etiology of these birth defects is multifactorial, involving genetic and environmental factors. However, in most cases, the underlying causes remain unexplained, precluding a molecular understanding of disease mechanisms. Here, we integrated genome-wide association data, targeted resequencing of case and control cohorts, tissue- and cell-type-specific epigenomic profiling, and genome architecture analyses to molecularly dissect a genomic locus associated with an increased risk of non-syndromic orofacial cleft. We found that common and rare risk variants associated with orofacial cleft intersect with an enhancer (e2p24.2) that is active in human embryonic craniofacial tissue. We mapped e2p24.2 long-range interactions to a topologically associated domain harboring MYCN, DDX1, and CYRIA. We found that MYCN and DDX1, but not CYRIA, are required during craniofacial development in chicken embryos. We investigated the role of DDX1, a key component of the tRNA splicing complex, in cranial neural crest cells (cNCCs). The loss of DDX1 in cNCCs resulted in the accumulation of unspliced tRNA fragments, depletion of mature intron-containing tRNAs, and ribosome stalling at codons decoded by these tRNAs. This was accompanied by defects in both global protein synthesis and cNCC migration. We further showed that the induction of tRNA fragments is sufficient to disrupt craniofacial development. Together, these results uncovered a molecular mechanism in which impaired tRNA splicing affects cNCCs and craniofacial development and positioned MYCN, DDX1, and tRNA processing defects as risk factors in the pathogenesis of orofacial clefts.

Genome-Wide Association Study of Glucocerebrosidase Activity Modifiers

One of the most common genetic risk factors for Parkinson's disease (PD) is variants in GBA1, which encodes the lysosomal enzyme glucocerebrosidase (GCase). GCase deficiency has been associated with an increased PD risk, but not all individuals with low GCase activity are carriers of GBA1 mutations, suggesting other factors may be acting as modifiers. We aimed to discover common variants associated with GCase activity, as well as replicate previously reported associations, by performing a genome-wide association study using two independent cohorts: a Columbia University cohort consisting of 697 PD cases and 347 controls and the Parkinson's Progression Markers Initiative (PPMI) cohort consisting of 357 PD cases and 163 controls. As expected, GBA1 variants have the strongest association with decreased activity, led by N370S (beta =  - 4.36, se = 0.32, p = 5.05e - 43). We also identify a novel association in the GAA locus (encoding for acid alpha-glucosidase, beta =  - 0.96, se = 0.17, p = 5.23e - 09) that may be the result of an interaction between GCase and acid alpha-glucosidase based on various interaction analyses. Lastly, we show that several PD-risk loci are potentially associated with GCase activity. Further research will be needed to replicate and validate our findings and to uncover the functional connection between acid alpha-glucosidase and GCase.

GWAS study of myelosuppression among NSCLC patients receiving platinum-based combination chemotherapy

Platinum-based chemotherapy remains the mainstay for non-small cell lung cancer (NSCLC), but it frequently causes dose-limiting myelosuppression, with significant individual variability in susceptibility. However, the genetic basis of myelosuppression side effects remains elusive, greatly hindering personalized therapeutic approaches. In this study, we perform a comprehensive genome-wide association analysis on 491 NSCLC patients receiving platinum-based chemotherapy, examining 4,690,998 single-nucleotide polymorphisms (SNPs) to identify relevant genetic variants. LDBlockShow, FUMA, and MAGMA are utilized to explore linkage disequilibrium, expression quantitative trait loci (eQTLs), chromatin interaction, and conduct gene-based and gene set-based analysis of candidate SNPs. The GWAS results reveal that rs6856089 and its linked SNPs are significantly associated with platinum-based chemotherapy-induced myelosuppression. Specifically, patients with the A allele of rs6856089 have a significantly lower risk of myelosuppression (odds ratio (OR) = 0.1300, P = 7.59 × 10 -8). Furthermore, gene-based analysis reveals that EMCN ( P = 2.47 × 10 -5), which encodes endomucin, a marker for hematopoietic stem cells, might mediate myelosuppression. This study provides a scientific basis for the individual differences in platinum-based chemotherapy-induced myelosuppression.

Genome-Wide Association Study of Atrial Fibrillation Recurrence After Radiofrequency Catheter Ablation in a Japanese Population

INTRODUCTION

Catheter ablation of atrial fibrillation (AF) is an established treatment; however, recurrence remains a major issue.

METHODS

This study included 606 patients with AF who underwent catheter ablation in Hiroshima University Hospital, including 143 and 463 patients with and without AF recurrence within 3 years after ablation, respectively. A logistic regression analysis and genome-wide association study (GWAS) were conducted to identify the clinical and genetic factors, respectively, associated with the AF recurrence risk.

RESULTS

A logistic regression analysis revealed persistent AF, nonpulmonary vein AF triggers, the N-terminal pro-brain natriuretic peptide level, and the left atrial volume before catheter ablation were significant factors for recurrence (false discovery rate < 0.05). Additionally, six variants (rs2106865, rs12577119, rs12574466, rs4902609, rs8027532, and rs2032303) were associated with the AF recurrence risk, based on the GWAS results' suggestive significance (p < 5 × 10-6). An expression quantitative trait locus analysis revealed a significant association between rs2106865 and ATP-binding cassette subfamily C member 8 (ABCC8) expression in heart tissues (atrial appendage and left ventricle). A linear regression analysis demonstrated a significant association between the ABCC8 variant rs2106865 and left atrium volume before ablation. Finally, the Cox proportional hazard model showed a significant association between the ABCC8 variant and AF recurrence (p = 1.30 × 10-5 by log-rank test; hazard ratio 1.74, 95% confidence interval 1.38-2.20).

CONCLUSIONS

Our findings, which highlight both the clinical and genetic factors associated with AF recurrence in Japanese patients, may contribute to future efforts to improve treatment strategies for AF.

Genetic variants associated with metabolic dysfunction-associated fatty liver diseases in a Korean population

BACKGROUND

Susceptibility to metabolic dysfunction-associated fatty liver diseases (MAFLD) shows a large inter-ethnic variability. Currently, large-scale genome-wide association studies (GWAS) on MAFLD in a Korean population are limited. This study aimed to investigate genes underlying MAFLD in a Korean population.

METHODS

A total of 13,457 Korean adults (4061 cases and 9396 controls) who underwent abdominal ultrasonography, biochemical testing, and genetic studies at a comprehensive health promotion center from 2019 to 2023 were included. Genome-wide genotyping was conducted using Infinium Asian Screening Array and an iSCAN system (Illumina, San Diego, CA, USA). Gene-based approach was conducted with Multi-Marker Analysis for Genomic Annotation (MAGMA) and Functional Mapping and Annotation (FUMA). Expression quantitative trait loci (eQTLs) mapping was done using GTEx v8 data.

RESULTS

The 22q13.3, 19p13.11, and 2p23.3 loci were associated with MAFLD after adjusting for age, sex, and body mass index (p < 5 × 10-8). Of these, 154 (89%) variants were identified as eQTLs (FDR < 0.05). Gene-based approach showed that PNPLA3, SAMM50, and PARVB were significantly associated with MAFLD (Bonferroni-corrected p < 2.99 × 10-6), followed by PDLIM4, GCKR, APOB, GPAM, HMGA1, C5orf56, and APOC1.

CONCLUSIONS

This is the largest-scale GWAS of MAFLD in a Korean adult population. Genotyping PARVB as well as PNPLA3 might help us identify individuals with the highest risk of MAFLD in Korean adults. These findings would contribute to our understanding of genetic pathogenesis of MAFLD in the Korean population.

GCH1 contributes to high-altitude adaptation in Tibetans by regulating blood nitric oxide

Nitric oxide (NO) is a key vasodilator that regulates vascular pressure and blood flow. Tibetans have developed a "blunted" mechanism for regulating NO levels at high altitude, with GTP cyclohydrolase 1 (GCH1) identified as a key candidate gene. Here, we present comprehensive genetic and functional analyses of GCH1, which exhibits strong Darwinian positive selection in Tibetans. We show that Tibetan-enriched GCH1 variants down-regulate its expression in the blood of Tibetans. Based on this observation, we generate the heterozygous Gch1 knockout (Gch1+/-) mouse model to simulate its downregulation in Tibetans. We find that under prolonged hypoxia, the Gch1+/- mice have relatively higher blood NO and blood oxygen saturation levels compared to the wild-type (WT) controls, providing better oxygen supplies to the cardiovascular and pulmonary systems. Markedly, hypoxia-induced cardiac hypertrophy and pulmonary remodeling are significantly attenuated in the Gch1+/- mice compared with the WT controls, likely due to the adaptive changes in molecular regulations related to metabolism, inflammation, circadian rhythm, extracellular matrix, and oxidative stress. This study sheds light on the role of GCH1 in regulating blood NO, contributing to the physiological adaptation of the cardiovascular and pulmonary systems in Tibetans at high altitude.

SURFBAT: a surrogate family based association test building on large imputation reference panels

Genotype-phenotype association tests are typically adjusted for population stratification using principal components that are estimated genome-wide. This lacks resolution when analyzing populations with fine structure and/or individuals with fine levels of admixture. This can affect power and precision, and is a particularly relevant consideration when control individuals are recruited using geographic selection criteria. Such is the case in France where we have recently created reference panels of individuals anchored to different geographic regions. To make correct comparisons against case groups, who would likely be gathered from large urban areas, new methods are needed. We present SURFBAT (a surrogate family based association test), which performs an approximation of the transmission-disequilibrium test. Our method hinges on the application of genotype imputation algorithms to match similar haplotypes between the case and control groups. This permits us to approximate local ancestry informed posterior probabilities of un-transmitted parental alleles of each case individual. This is achieved by assuming haplotypes from the imputation panel are well-matched for ancestry with the case individuals. When the first haplotype of an individual from the imputation panel matches that of a case individual, it is assumed that the second haplotype of the same reference individual can be used as a locally ancestry matched control haplotype and to approximately impute un-transmitted parental alleles. SURFBAT provides an association test that is inherently robust to fine-scale population stratification and opens up the possibility of efficiently using large imputation reference panels as control groups for association testing. In contrast to other methods for association testing that incorporate local-ancestry inference, SURFBAT does not require a set of ancestry groups to be defined, nor for local ancestry to be explicitly estimated. We demonstrate the interest of our tool on simulated datasets, as well as on a real-data example for a group of case individuals affected by Brugada syndrome.

Genome-wide association study identifies common variants associated with breast cancer in South African Black women

Genome-wide association studies (GWAS) have characterized the contribution of common variants to breast cancer (BC) risk in populations of European ancestry, however GWAS have not been reported in resident African populations. This GWAS included 2485 resident African BC cases and 1101 population matched controls. Two risk loci were identified, located between UNC13C and RAB27A on chromosome 15 (rs7181788, p = 1.01 × 10-08) and in USP22 on chromosome 17 (rs899342, p = 4.62 × 10-08). Several genome-wide significant signals were also detected in hormone receptor subtype analysis. The novel loci did not replicate in BC GWAS data from populations of West Africa ancestry suggesting genetic heterogeneity in different African populations, but further validation of these findings is needed. A European ancestry derived polygenic risk model for BC explained only 0.79% of variance in our data. Larger studies in pan-African populations are needed to further define the genetic contribution to BC risk.

Exploring the molecular basis of the genetic correlation between body mass index and brain morphological traits

Several studies have demonstrated significant phenotypic and genetic correlations between body mass index (BMI) and brain morphological traits derived from structural magnetic resonance imaging (sMRI). We use the sMRI, BMI, and genetic data collected by the UK Biobank to systematically compute the genetic correlations between area, volume, and thickness measurements of hundreds of brain structures on one hand, and BMI on the other. In agreement with previous literature, we find many such measurements to have negative genetic correlation with BMI. We then dissect the molecular mechanisms underlying such correlations using brain eQTL data and summary-based Mendelian randomization, thus producing an atlas of genes whose genetically regulated expression in brain tissues is pleiotropic with brain morphology and BMI. Fine-mapping followed by colocalization analysis allows, in several cases, the identification of credible sets of variants likely to be causal for both the macroscopic phenotypes and for gene expression. In particular, epigenetic fine mapping identifies variant rs7187776 in the 5' UTR of the TUFM gene as likely to be causal of increased BMI and decreased caudate volume, possibly through the creation, by the alternate allele, of an ETS binding site leading to increased chromatin accessibility, specifically in microglial cells.

Genomic and molecular evidence that the lncRNA DSP-AS1 modulates Desmoplakin expression

Cardiac desmosomes are specialized cell junctions responsible for cardiomyocytes mechanical coupling. Mutation in desmosomal genes cause autosomal dominant and recessive familial arrhythmogenic cardiomyopathy. Motivated by evidence that Mendelian diseases share genetic architecture with common complex traits, we assessed whether common variants in any desmosomal gene were associated with cardiac conduction traits in the general population. We analysed data of N=4342 Cooperative Health Research in South Tyrol (CHRIS) study participants. We tested associations between genotype imputed variants covering the five desmosomal genes DSP, JUP, PKP2, DSG2, and DSC2, and P-wave, PR, QRS, and QT electrocardiographic intervals, using linear mixed models. Functional annotation and interrogation of publicly available genome-wide association study resources implicated potential connection with antisense lncRNAs, DNA methylation sites, and complex traits. Causality was tested via two-sample Mendelian randomization (MR) analysis and validated with functional in vitro follow-up in human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs). DSP variant rs2744389 was associated with QRS (P=3.5×10-6), with replication in the Microisolates in South Tyrol (MICROS) study (n=636; P=0.010). Observing that rs2744389 was associated with DSP-AS1 antisense lncRNA but not with DSP expression in multiple GTEx-v8 tissues, we conducted two-sample Mendelian randomization analyses that identified causal effects of DSP-AS1 on DSP expression (P=6.33×10-5; colocalization posterior probability=0.91) and QRS (P=0.015). In hiPSC-CMs, DSP-AS1 expression downregulation through a specific GapmerR matching sequence led to significant DSP upregulation at both mRNA and protein levels. The evidence that DSP-AS1 has a regulatory role on DSP opens the venue for further investigations on DSP-AS1's therapeutic potential for conditions caused by reduced desmoplakin production.

Differing genetics of saline and cocaine self-administration in the hybrid mouse diversity panel

To identify genes that regulate the response to the potentially addictive drug cocaine, we performed a control experiment using genome-wide association studies (GWASs) and RNA-Seq of a panel of inbred and recombinant inbred mice undergoing intravenous self-administration of saline. A linear mixed model increased statistical power for analysis of the longitudinal behavioral data, which was acquired over 10 days. A total of 145 loci were identified for saline compared to 17 for the corresponding cocaine GWAS. Only one locus overlapped. Transcriptome-wide association studies (TWASs) using RNA-Seq data from the nucleus accumbens and medial frontal cortex identified 5031434O11Rik and Zfp60 as significant for saline self-administration. Two other genes, Myh4 and Npc1, were nominated based on proximity to loci for multiple endpoints or a cis locus regulating expression. All four genes have previously been implicated in locomotor activity, despite the absence of a strong relationship between saline taking and distance traveled in the open field. Our results indicate a distinct genetic basis for saline and cocaine self-administration, and suggest some common genes for saline self-administration and locomotor activity.

Mitochondrial reactive oxygen species regulate acetyl-CoA flux between cytokine production and fatty acid synthesis in effector T cells

Genetic and environmental factors shape an individual's susceptibility to autoimmunity. To identify genetic variations regulating effector T cell functions, we used a forward genetics screen of inbred mouse strains and uncovered genomic loci linked to cytokine expression. Among the candidate genes, we characterized a mitochondrial inner membrane protein, TMEM11, as an important determinant of Th1 responses. Loss of TMEM11 selectively impairs Th1 cell functions, reducing autoimmune symptoms in mice. Mechanistically, Tmem11-/- Th1 cells exhibit altered cristae architecture, impaired respiration, and increased mitochondrial reactive oxygen species (mtROS) production. Elevated mtROS hindered histone acetylation while promoting neutral lipid accumulation. Further experiments using genetic, biochemical, and pharmacological tools revealed that mtROS regulate acetyl-CoA flux between histone acetylation and fatty acid synthesis. Our findings highlight the role of mitochondrial cristae integrity in directing metabolic pathways that influence chromatin modifications and lipid biosynthesis in Th1 cells, providing new insights into immune cell metabolism.

Unraveling the genetic links between depression and type 2 diabetes

BACKGROUND

Type 2 diabetes (T2D) is a chronic metabolic disorder that has high comorbidity with mental disorders. The genetic relationships between T2D and depression are far from being well understood.

METHODS

We performed genetic correlation, polygenic overlap, Mendelian randomization (MR) analyses, cross-trait meta-analysis, and Bayesian colocalization analysis to assess genetic relationships between T2D and depression, in the forms of major depressive disorder (MDD) and depressed affect (DAF). Then, the summary data-based MR (SMR) analysis was performed to prioritize genes contributing to MDD and to T2D from functional perspective. MDD-driven signaling pathways were constructed to understand the influence of MDD on T2D at the molecular level.

RESULTS

T2D has positive genetic correlations both with MDD (rg = 0.14) and with DAF (rg = 0.19). The polygenic overlap analysis showed that about 60 % of causal variants for T2D are shared with MDD and DAF. The MR analysis indicated that genetic liabilities to both MDD (OR: 1.24, 95 % CI: 1.11-1.38) and DAF (OR: 1.48, 95 % CI: 1.23-1.78) are associated with an increased risk for T2D, while genetic liability to T2D is not associated with the risk for MDD (OR: 1.00, 95 % CI: 0.99-1.01) or DAF (OR: 1.01, 95 % CI: 1.00-1.02). The cross-trait meta-analysis identified 271 genomic loci, of which 29 were novel. Genetic predisposition to MDD and T2D shares six overlapping loci, involving some well-characterized genes, such as TCF4 and NEGR1. Colocalization analysis revealed three shared chromosome regions between MDD and T2D, which covers mediator genes including SCYL1, DENND1A, and MAD1L1. Molecular pathway analysis suggests mechanisms that promote the development of T2D through inflammatory pathways overactive in patients with MDD. The SMR analysis and the meta-analysis highlighted seven genes with functional implications for both MDD and T2D, including TNKS2, CCDC92, FADS1, ERI1, THUMPD3, NUCKS1, and PM20D1.

CONCLUSIONS

Our study points out that depression, in the forms of MDD and DAF, may increase the risk of T2D. Analysis of underlying genetic variation and the molecular pathways, connecting depression and T2D, indicate that the pathophysiological foundations of these two conditions have a notable overlap.

The regulatory role of ACP5 in the diesel exhaust particle-induced AHR inflammatory signaling pathway in a human bronchial epithelial cell line

Exposure to diesel exhaust particles (DEPs), which are major constituents of urban air pollution, is associated with adverse health outcomes. Previous studies have shown that DEPs enhance the expression of pro-inflammatory cytokines and immune responses. However, few studies have focused on genomic variants that regulate DEP-induced signaling. Here, we identify a frequently found genomic variant, ACP5, in allergic diseases, and establish an ACP5 knock-out (KO) human bronchial epithelial cell line (BEAS-2B) using CRISPR/Cas9 editing to mimic the ACP5 mutation. DEP-induced apoptosis and intracellular reactive oxygen species (ROS) were significantly increased in the ACP5 KO cells compared with controls, suggesting that ACP5 KO cells were at increased risk from DEP exposure. A gene expression profile revealed an activated aryl hydrocarbon receptor (AHR)-CYP1A1 axis followed by upregulated pro-inflammatory signaling. Treatment of a DEP-exposed ACP5 KO BEAS-2B conditioned medium (CM) supernatant induced an inflammatory response and tissue damage in mice, and AHR inhibition effectively prevented inflammation-induced damage, suggesting that AHR-CYP1A1-inflammatory signaling is a prominent mechanism responsible for detrimental effects. Collectively, our findings reveal a novel link between ACP5 KO and the AHR-CYP1A1 inflammatory signaling pathway in DEP-exposed cells, and identify the AHR-CYP1A1 axis as a potential therapeutic target in individuals suffering from DEP-induced toxicity, particularly those with ACP5 mutations.

Discovery of ancestry-specific variants associated with clopidogrel response among Caribbean Hispanics

High on-treatment platelet reactivity (HTPR) with clopidogrel predicts ischemic events in adults with coronary artery disease, and while HTPR varies by ethnicity, no genome-wide association study (GWAS) of clopidogrel response has been conducted in Caribbean Hispanics. This study aimed to identify genetic predictors of HTPR in a cohort of 511 Puerto Rican cardiovascular patients treated with clopidogrel, stratified by P2Y12 reaction units (PRU) into responders and non-responders (HTPR). Local ancestry inference (LAI) and traditional GWAS identified variants in the CYP2C19 region associated with HTPR, primarily in individuals with European ancestry. Three variants (OSBPL10 rs1376606, DERL3 rs5030613, RGS6 rs9323567) showed suggestive significance, and a variant in UNC5C was linked to increased HTPR risk. These findings highlight the unique genetic landscape of Caribbean Hispanics and challenge the significance of CYP2C19*2 in predicting clopidogrel response in patients with high non-European ancestry. Further studies are needed to replicate these results in other diverse cohorts.

Empowering genome-wide association studies via a visualizable test based on the regional association score

The genome-wide association studies identified genes associated with many diseases, but the identification and verification of disease variants are still challenging due to small effects and large number of individual variants. In this paper, we propose a powerful method that first quantifies the strength of regional associations at each single nucleotide polymorphism and converts these measures into time series data before using a change point detection algorithm to identify significant regions. In our extensive simulation study, the proposed method consistently demonstrates greater power than existing alternatives, achieving a relative increase of over 20% in challenging scenarios where true causal variants are sparse and multiple association regions exist at the same time, while maintaining a lower false positive rate.

Local genetic covariance analysis with lipid traits identifies novel loci for early-onset Alzheimer's Disease

The genetic component of early-onset Alzheimer disease (EOAD), accounting for ~10% of all Alzheimer's disease (AD) cases, is largely unexplained. Recent studies suggest that EOAD may be enriched for variants acting in the lipid pathway. The current study examines the shared genetic heritability between EOAD and the lipid pathway using genome-wide multi-trait genetic covariance analyses. Summary statistics were obtained from the GWAS meta-analyses of EOAD by the Alzheimer's Disease Genetics Consortium (n=19,668) and five blood lipid traits by the Global Lipids Genetics Consortium (n=1,320,016). The significant results were compared between the EOAD and lipids GWAS and genetic covariance analyses were performed via SUPERGNOVA. Genes in linkage disequilibrium (LD) with top EOAD hits in identified regions of covariance with lipid traits were scored and ranked for causality by combining evidence from gene-based analysis, AD-risk scores incorporating transcriptomic and proteomic evidence, eQTL data, eQTL colocalization analyses, DNA methylation data, and single-cell RNA sequencing analyses. Direct comparison of GWAS results showed 5 loci overlapping between EOAD and at least one lipid trait harboring APOE, TREM2, MS4A4E, LILRA5, and LRRC25. Local genetic covariance analyses identified 3 regions of covariance between EOAD and at least one lipid trait. Gene prioritization nominated 3 likely causative genes at these loci: ANKDD1B, CUZD1, and MS4A64.The current study identified genetic covariance between EOAD and lipids, providing further evidence of shared genetic architecture and mechanistic pathways between the two traits.

FLT1 and other candidate fetal haemoglobin modifying loci in sickle cell disease in African ancestries

Known fetal haemoglobin (HbF)-modulating loci explain 10-24% variation of HbF level in Africans with Sickle Cell Disease (SCD), compared to 50% among Europeans. Here, we report fourteen candidate loci from a genome-wide association study (GWAS) of HbF level in patients with SCD from Cameroon, Tanzania, and the United States of America. We present results of cell-based experiments for FLT1 candidate, demonstrating expression in early haematopoiesis and a possible involvement in hypoxia associated HbF induction. Our study employed genotyping arrays that capture a broad range of African and non-African genetic variation and replicated known loci (BCL11A and HBS1L-MYB). We estimated the heritability of HbF level in SCD at 94%, higher than estimated in unselected Europeans, and suggesting a robust capture of HbF-associated loci by these arrays. Our approach, which involved genotype imputation against six reference haplotype panels and association analysis with each of the panels, proved superior over selecting a best-performing panel, evidenced by a substantial proportion of panel-specific (up to 18%) and a low proportion of shared (28%) imputed variants across the panels.

Genome-Wide Association Study Identifying a Novel Gene Related to a History of Febrile Convulsions in Patients With Focal Epilepsy

BACKGROUND AND PURPOSE

The risk factors for developing epilepsy following febrile convulsion (FC) have been studied extensively, but the underlying genetic components remain largely unexplored. Our objective here was to identify the risk loci related to FC through a genome-wide association study of Korean epilepsy patients.

METHODS

We examined associations between a history of FC and single-nucleotide polymorphisms (SNPs) in data obtained from 125 patients with focal epilepsy: 28 with an FC history and 97 without an FC history.

RESULTS

Among 288,394 SNPs, 5 candidate SNPs showed p<1×10⁻⁴. Regional association plots of these SNPs identified a novel locus adjacent to PROX1 that is implicated in hippocampal neurogenesis and epileptogenesis. The allele frequencies of the SNPs upstream of PROX1 including two candidate SNPs (rs1159179 and rs7554295 on chromosome 1) differed significantly between the groups with and without an FC history. In contrast, the allele frequencies of the SNPs inside PROX1 showed no differences, indicating dysregulated expression of PROX1 rather than a functional alteration in the PROX1 protein.

CONCLUSIONS

This novel discovery of SNPs upstream of PROX1 suggests that the dysregulated expression of PROX1 contributes to the development of focal epilepsy following FC. We propose that these SNPs are potential genetic markers for focal epilepsy following FC, and that PROX1 represents a potential therapeutic target of antiseizure medications.

rs762855 single nucleotide polymorphism modulates the risk for diffuse-type gastric cancer in females: a genome-wide association study in the Korean population

BACKGROUND

Intestinal-type gastric cancer (IGC) and diffuse-type gastric cancer (DGC) exhibit different prevalence rates between sexes. While environmental factors like Helicobacter pylori infection and alcohol consumption contribute to these differences, they do not fully account for them, suggesting a role for host genetic factors.

METHODS

We conducted a meta-analysis to explore associations between single nucleotide polymorphisms (SNPs) and the risk of IGC or DGC. The analysis included the SNUBH cohort (998 participants: 159 DGCs, 303 IGCs, 4,962,361 variants) and the GC_HC cohort (6,233 participants: 389 DGCs, 405 IGCs, 4,541,617 variants). Significant variants were validated in the SNUBH2_AA cohort (5,511 participants: 40 DGCs, 49 IGCs, 3,668,632 variants).

RESULTS

The meta-analysis identified that rs762855 (chr4:3,074,795; hg19) is significantly associated with DGC risk in females (OR [95% CI]: 1.758 [1.438-2.150], P = 3.91 × 10-8), a finding replicated in the SNUBH2_AA datasets (OR [95% CI]: 3.356 [1.031-10.92], P = 4.43 × 10-2). Gene-set and transcriptomic analyses revealed that the Myb/SANT DNA Binding Domain Containing 1 (MSANTD1) gene is significantly linked to DGC susceptibility in females. In addition, Mendelian randomization analyses suggested that increased serum total protein and non-albumin protein (NAP) levels elevate DGC risk in females (P < 0.05), but not in males.

CONCLUSION

The rs762855 SNP, MSANTD1, and serum NAP levels are associated with DGC risk in Korean females.

A multi-ancestry genome-wide association study and evaluation of polygenic scores of LDL-C levels

The genetic determinants of low-density lipoprotein cholesterol (LDL-C) levels in blood have been predominantly explored in European populations and remain poorly understood in Middle Eastern populations. We investigated the genetic architecture of LDL-C variation in Qatar by conducting a genome-wide association study (GWAS) on serum LDL-C levels using whole genome sequencing data of 13,701 individuals (discovery; n = 5,939, replication; n = 7,762) from the population-based Qatar Biobank (QBB) cohort. We replicated 168 previously reported loci from the largest LDL-C GWAS by the Global Lipids Genetics Consortium (GLGC), with high correlation in allele frequencies (R2 = 0.77) and moderate correlation in effect sizes (Beta; R2 = 0.53). We also performed a multi-ancestry meta-analysis with the GLGC study using MR-MEGA (Meta-Regression of Multi-Ethnic Genetic Association) and identified one novel LDL-C-associated locus; rs10939663 (SLC2A9; genomic control-corrected P = 1.25 × 10-8). Lastly, we developed Qatari-specific polygenic score (PGS) panels and tested their performance against PGS derived from other ancestries. The multi-ancestry-derived PGS (PGS000888) performed best at predicting LDL-C levels, whilst the Qatari-derived PGS showed comparable performance. Overall, we report a novel gene associated with LDL-C levels, which may be explored further to decipher its potential role in the etiopathogenesis of cardiovascular diseases. Our findings also highlight the importance of population-based genetics in developing PGS for clinical utilization.

Rare genetic associations with human lifespan in UK Biobank are enriched for oncogenic genes

Human lifespan is shaped by genetic and environmental factors. To enable precision health, understanding how genetic variants influence mortality is essential. We conducted a survival analysis in European ancestry participants of the UK Biobank, using age-at-death (N=35,551) and last-known-age (N=358,282). The associations identified were predominantly driven by cancer. We found lifespan-associated loci (APOE, ZSCAN23) for common variants and six genes where burden of loss-of-function variants were linked to reduced lifespan (TET2, ATM, BRCA2, CKMT1B, BRCA1, ASXL1). Additionally, eight genes with pathogenic missense variants were associated with reduced lifespan (DNMT3A, SF3B1, TET2, PTEN, SOX21, TP53, SRSF2, RLIM). Many of these genes are involved in oncogenic pathways and clonal hematopoiesis. Our findings highlight the importance of understanding genetic factors driving the most prevalent causes of mortality at a population level, highlighting the potential of early genetic testing to identify germline and somatic variants increasing one's susceptibility to cancer and/or early death.

Epidemiology and genetic determination of measures of peripheral vascular health in the Long Life Family Study

Peripheral artery disease (PAD) is a major contributor to morbidity in older adults. We aimed to determine genetic and non-genetic determinants of PAD and ankle-brachial index (ABI) in the Long Life Family Study (LLFS). 3006 individuals had ABI assessment, including 1090 probands (mean age 89), 1554 offspring (mean age 60) and 362 spousal controls (mean age 61). Outcomes include minimum of right and left ABIs and PAD (ABI <0.9). Stepwise regression determined independent significant non-genetic correlates of ABI and PAD. Genomewide association and linkage analyses were adjusted for age, sex, study center, significant principal components, and independent predictors. All analyses accounted for familial relatedness. Median ABI was 1.16 and 7.4% had PAD (18.2% probands, 1.0% offspring, 1.9% controls). Correlates of PAD and lower ABI included age, SBP, and creatinine (ABI only); BMI (ABI only), HDL (ABI only) and DBP (PAD only); and antihypertensive use, current smoking, female sex (ABI only), and high school noncompletion (ABI only). Genomewide linkage identified 1 region (15q12-q13) and association identified 3 single nucleotide polymorphisms (rs780213, rs12512857, rs79644420) of interest. In these families, PAD prevalence was low compared to other studies of older adults. We identified four genomic sites that may harbor variants associated with protection from PAD.

Identification of functional non-coding variants associated with orofacial cleft

Oral facial cleft (OFC) is a multifactorial disorder that can present as a cleft lip with or without cleft palate (CL/P) or a cleft palate only. Genome wide association studies (GWAS) of isolated OFC have identified common single nucleotide polymorphisms (SNPs) at the 1q32/ IRF6 locus and many other loci where, like IRF6 , the presumed OFC-relevant gene is expressed in embryonic oral epithelium. To identify the functional subset of SNPs at eight such loci we conducted a massively parallel reporter assay in a cell line derived from fetal oral epithelium, revealing SNPs with allele-specific effects on enhancer activity. We filtered these against chromatin-mark evidence of enhancers in relevant cell types or tissues, and then tested a subset in traditional reporter assays, yielding six candidates for functional SNPs in five loci (1q32/ IRF6 , 3q28/ TP63 , 6p24.3/ TFAP2A , 20q12/ MAFB , and 9q22.33/ FOXE1 ). We further tested two SNPs near IRF6 and one near FOXE1 by engineering the genome of induced pluripotent stem cells, differentiating the cells into embryonic oral epithelium, and measuring expression of IRF6 or FOXE1 and binding of transcription factors; the results strongly supported their candidacy. Conditional analyses of a meta-analysis of GWAS suggest that the two functional SNPs near IRF6 account for the majority of risk for CL/P associated with variation at this locus. This study connects genetic variation associated with orofacial cleft to mechanisms of pathogenesis.

RTF1 mediates epigenetic control of Th17 cell differentiation via H2B monoubiquitination

A gene encoding the transcription factor RTF1 has been associated with an increased risk of ulcerative colitis (UC). In this study, we investigated its function in modulating T cells expressing interleukin-17A (Th17 cells), a cardinal cell type promoting intestinal inflammation. Our results indicate that Rtf1 deficiency disrupts the differentiation of Th17 cells, while leaving regulatory T cells (Treg) unaffected. Mechanistically, RTF1 facilitates histone H2B monoubiquitination (H2Bub1), which requires its histone modification domain (HMD), for supporting Th17 cell function. Impaired Th17 differentiation was also observed in cells lacking the H2Bub1 E3 ligase subunit RNF40, an enzyme known to physically interact with RTF1. Thus, our study underscores the essential role of RTF1 in H2Bub1-mediated epigenetic regulation of Th17 cell differentiation. Understanding this process will likely provide valuable insights into addressing Th17-associated inflammatory disorders. (Images were created with BioRender).

A variant in HMMR/HMMR-AS1 is associated with serum alanine aminotransferase levels in the Ryukyu population

The Ryukyu archipelago is located southwest of the Japanese islands, and people originally from this region, the Ryukyu population, have a unique genetic background distinct from that of other populations, including people from mainland Japan. However, few genetic studies have focused on the Ryukyu population. In this study, we performed genome-wide association studies (GWAS) on the serum levels of alanine aminotransferase (ALT, n = 15,224), aspartate aminotransferase (AST, n = 15,203), and gamma-glutamyl transferase (GGT, n = 14,496) in the Ryukyu population. We found 13 loci with a genome-wide significant association (P < 5 × 10-8), three for ALT, four for AST, and six for GGT, including one novel locus associated with ALT: rs117595134-A in HMMR/HMMR-AS1, ß =  - 0.131, standard error = 0.024, P = 4.90 × 10-8. Rs117595134-A is common in the Japanese population but is not observed in other ethnic populations in the 1000 genomes database. Additionally, 77 of 80 loci derived from Korean GWAS and 541 of 716 loci from European GWAS showed the same directions of effect (P = 1.41 × 10-19, P = 2.50 × 10-44, binomial test), indicating that most of susceptibility loci are shared between the Ryukyu population and other ethnic populations.

PSMB4: a potential biomarker and therapeutic target for depression, perspective from integration analysis of depression GWAS data and human plasma proteome

Depression is a common and severe mental disorder that affects more than 300 million people worldwide. While it is known to have a moderate genetic component, identifying specific genes that contribute to the disorder has been challenging. Previous Genome-wide association studies (GWASs) have identified over 100 genomic loci that are significantly associated with depression. But finding useful therapeutic targets and diagnostic biomarkers from this information has proven difficult. To address this challenge, I conducted a plasma protein proteome-wide association study (PWAS) for depression, using human plasma protein QTL (pQTL) and depression GWAS data. I identified four proteins that were significantly associated with depression: BTN3A3 (P value = 6.41 × 10-06), PSMB4 (P value = 1.42 × 10-05), TIMP4 (P value = 3.77 × 10-05), and ITIH1 (P value = 7.86 × 10-05). Specifically, I found that BTN3A3 and PSMB4 play a causal role in depression, as confirmed by colocalization and Mendelian Randomization (MR) analysis. Interestingly, I also discovered that PSMB4 was significantly associated with depression in both the brain proteome studies and the plasma PWAS results, which suggests that it may be a particularly promising candidate for further study. Overall, this work has identified 4 new risk proteins for depression and highlights the potential of plasma proteome data for uncovering novel therapeutic targets and diagnostic biomarkers.

A genome-wide association study identified PRKCB as a causal gene and therapeutic target for Mycobacterium avium complex disease

Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is a chronic progressive lung disease that is increasing in incidence. Host genetic factors are associated with NTM-PD susceptibility. However, the heritability of NTM-PD is not well understood. Here, we perform a two-stage genome-wide association study (GWAS) and discover a susceptibility locus at 16p21 associated with NTM-PD, especially with pulmonary Mycobacterium avium complex (MAC) disease. As the lead variant, rs194800 C allele augments protein kinase C beta (PRKCB) gene expression and associates with severer NTM-PD. The functional studies show that PRKCB exacerbates M. avium infection and promotes intracellular survival of M. avium in macrophages by inhibiting phagosomal acidification. Mechanistically, PRKCB interacts with subunit G of the vacuolar-H+-ATPase (V-ATPase) and vacuolar protein sorting-associated protein 16 homolog (VPS16), blocking the fusion between lysosomes and mycobacterial phagosomes. PRKCB inhibitor has therapeutic potential against M. avium infection. These findings provide insights into the genetic etiology of NTM-PD and highlight PRKCB as an attractive target for host-directed therapy of MAC disease.

Human mood disorder risk gene Synaptotagmin-14 contributes to mania-like behaviors in mice

Bipolar disorder (BD) and major depressive disorder (MDD) are the most prevalent mood disorders and cause considerable burden worldwide. Compelling evidence suggests a pronounced overlap between these two disorders in clinical symptoms, treatment strategies, and genetic etiology. Here we leverage a BD GWAS (1822 cases and 4650 controls) and a MDD GWAS (5303 cases and 5337 controls), followed by independent replications, to investigate their shared genetic basis among Han Chinese. We have herein identified a lead SNP rs126277 at the 1q32.2 locus, which also exhibited nominal associations with mood disorders and several relevant sub-clinical phenotypes (e.g., mania) in European populations. Bulk tissue and single-cell eQTL analyses suggest that the risk G-allele of rs126277 predicted lower SYT14 mRNA expression in human brains. We generated mice lacking Syt14 (Syt14-/-) and mice with insufficient expression of Syt14 in the hippocampus (Syt14-KD), and found that depletion of Syt14 resulted in mania-like behaviors including hyperactivity and anti-depressive behaviors, resembling aspects of mood disorders. We also confirmed that deficiency of this gene in the hippocampus was sufficient to induce hyperactivity in mice. RNA-sequencing analyses of the hippocampus of Syt14-/- mice revealed significant upregulation of Per1 as well as downregulation of Slc7a11 and Ptprb. Ultrastructural analyses showed significant alteration of the number of vesicles within 50 nm to the active zone and the width of synaptic cleft in the ventral hippocampus of Syt14-/- mice compared with the control mice. Overall, we have identified a novel mood disorder risk gene SYT14, and confirmed its impact on mania-like behaviors. While the current study identifies an essential mood disorder risk gene, further investigations elucidating the detailed mechanisms by which SYT14 contributes to the pathogenesis of the illnesses are needed.

Exploring genetic loci linked to COVID-19 severity and immune response through multi-trait GWAS analyses

Introduction

COVID-19 severity has been linked to immune factors, with excessive immune responses like cytokine storms contributing to mortality. However, the genetic basis of these immune responses is not well understood. This study aimed to explore the genetic connection between COVID-19 severity and blood cell traits, given their close relationship with immunity.

Materials and methods

GWAS summary statistics for COVID-19 and blood cell counts were analyzed using Linkage Disequilibrium Score Regression (LDSC) to estimate genetic correlations and heritabilities. For traits with significant correlations, a Multi-Trait GWAS Analysis (MTAG) was performed to identify pleiotropic loci shared between COVID-19 and blood cell counts.

Results

Our MTAG analysis identified four pleiotropic loci associated with COVID-19 severity, five loci linked to hospitalized cases, and one locus related to general patients. Among these, two novel loci were identified in the high-risk population, with rs55779981 located near RAVER1 and rs73009538 near CARM1. In hospitalized patients, two previously unrecognized loci were detected, namely, rs115545251 near GFI1 and rs3181049 near RAVER1, while in general patients, rs11065822 near CUX2 emerged as a newly identified locus. We also identified potential target genes, including those involved in inflammation signaling (CARM1), endothelial dysfunction (INTS12), and antiviral immune response (RAVER1), which may require further investigation.

Conclusion

Our study offers insights into the genetic overlap between COVID-19 and immune factors, suggesting potential directions for future research and clinical exploration.

WNT inhibitor SP5-mediated SERPING1 suppresses lung adenocarcinoma progression via TSC2/mTOR pathway

The long-term outlook for patients grappling with lung cancer (LC) remains bleak, with lung adenocarcinoma (LUAD) emerging as the most predominant histological subtype. Our Mendelian randomization (MR) investigation spotlighted that heightened levels of the circulating protein serpin peptidase inhibitor family G1 (SERPING1) substantially mitigated LC risk. The fusion of multi-omics strategies unveiled that SERPING1 exhibited diminished expression in LUAD patients compared to healthy individuals both in tissues and serum, with LUAD individuals showcasing elevated SERPING1 expression demonstrating improved prognoses. Furthermore, SERPING1 expression exhibited a robust correlation with the efficacy of immunotherapy. Through meticulous in vivo and in vitro analyses, we unraveled that SERPING1 impeded the proliferation, migration, invasion and wound healing of LUAD cells via the tuberous sclerosis 2 (TSC2)/mammalian target of rapamycin (mTOR) pathway. Mechanistically, WNT inhibitor- Specificity Protein (SP5) was delineated as facilitator of SERPING1 transcription by binding to the SERPING1 gene promoter. Intriguingly, aside from the association between SERPING1 and systolic blood pressure, glycosylated hemoglobin (HbA1c), type I diabetes, no discernible link between SERPING1 overexpression and heightened risks of other cardiometabolic conditions and diseases was evident. In summary, SERPING1 emerges as a novel tumor suppressor gene and SP5/SERPING1/TSC2 is a promising therapeutic target in the context of LUAD.

MTHFR Polymorphisms, Homocysteine Elevation, and Ischemic Stroke Susceptibility in East Asian and European Populations

BACKGROUND AND OBJECTIVES

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme that regulates folate and homocysteine metabolism. Genetic variation in MTHFR has been implicated in cerebrovascular disease risk, although research in diverse populations is lacking. We thus aimed to investigate the effect of genetically predicted MTHFR activity on risk of ischemic stroke (IS) and its main subtypes using a multiancestry Mendelian randomization (MR) approach.

METHODS

We proxied reduced MTHFR function using the C677T missense variant that impairs MTHFR function and consequently increases levels of total plasma homocysteine (tHcy) in both East Asian and European populations. Summary data for IS and its subtypes (small vessel stroke [SVS], large artery stroke [LAS], and cardioembolic stroke [CES]) were obtained from the largest available genome-wide association studies. MR estimates were calculated using the Wald ratio and random-effects inverse-variance-weighted methods. We performed sensitivity analyses to evaluate for confounding due to linkage disequilibrium.

RESULTS

Genetically downregulated MTHFR activity, associated with a consequent SD increase in tHcy levels, was associated with an increased risk of SVS in both East Asian (odds ratio [OR] 1.20, 95% CI 1.08-1.34, p = 8.58 × 10-4) and European populations (OR 1.62, 95% CI 1.24-2.12; p = 3.73 × 10-4). There was no evidence that genetically perturbed MTHFR activity influenced risk of CES or LAS. These findings were consistent in sensitivity analyses.

DISCUSSION

Our findings provide genetic evidence that reduced MTHFR activity was selectively associated with an increased risk of SVS in both East Asian and European populations. These findings warrant further investigation of genotype-guided nutritional supplementation for the prevention of SVS.

Tau pathway-based gene analysis on PET identifies CLU and FYN in a Korean cohort

INTRODUCTION

The influence of genetic variation on tau protein aggregation, a key factor in Alzheimer's disease (AD), remains not fully understood. We aimed to identify novel genes associated with brain tau deposition using pathway-based candidate gene association analysis in a Korean cohort.

METHODS

We analyzed data for 146 older adults from the well-established Korean AD continuum cohort (Korean Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease; KBASE). Fifteen candidate genes related to both tau pathways and AD were selected. Association analyses were performed using PLINK: A tool set for whole-genome association and population-based linkage analyses (PLINK) on tau deposition measured by 18F-AV-1451 positron emission tomography (PET) scans, with additional voxel-wise analysis conducted using Statistical Parametric Mapping 12 (SPM12).

RESULTS

CLU and FYN were significantly associated with tau deposition, with the most significant single-nucleotide polymorphisms (SNPs) being rs149413552 and rs57650567, respectively. These SNPs were linked to increased tau across key brain regions and showed additive effects with apolipoprotein E (APOE) ε4.

DISCUSSION

CLU and FYN may play specific roles in tau pathophysiology, offering potential targets for biomarkers and therapies.

HIGHLIGHTS

Gene-based analysis identified CLU and FYN as associated with tau deposition on positron emission tomography (PET). CLU rs149413552 and FYN rs57650567 were associated with brain tau deposition. rs149413552 and rs57650567 were associated with structural brain atrophy. CLU rs149413552 was associated with immediate verbal memory. CLU and FYN may play specific roles in tau pathophysiology.

Proteome-wide association studies have predicted that the protein abundance of LSM6, GMPPB, ICA1L, and CISD2 is associated with attention-deficit/hyperactivity disorder

Identification of changes in protein abundance for attention-deficit/hyperactivity disorder (ADHD) is important for potential disease mechanisms and therapeutic study for ADHD. In order to identify candidate proteins that confer risk for ADHD, a proteome-wide association study (PWAS) for ADHD was conducted by integrating two human brain proteome datasets and the ADHD genome-wide association study (GWAS) summary statistics released by the Psychiatric Genomics Consortium (PGC). A total of 11 risk proteins were identified as significant candidates that passed the bonferroni corrected proteome-wide significant (PWS) level. The predicted protein abundance level of LSM6, GMPPB, ICA1L and CISD2 are shown significantly associated with ADHD in both proteome datasets, highlighting their potential role in ADHD pathogenesis. A transcriptome-wide association study (TWAS) of ADHD was also conducted, and 13 genes with predicted expression changes related to ADHD were identified. GMPPB, ICA1L and NAT6 were supported by both TWAS and PWASs analysis. This study uncovers the predicted protein abundance changes that confer risk for ADHD and pinpoints a number of high-confidence protein candidates (e.g. LSM6, GMPPB, ICA1L, CISD2) for further functional exploration studies and drug development targeting these proteins.

Haplotype rather than single causal variants effects contribute to regulatory gene expression associations in human myeloid cells

Genome-wide association studies typically identify hundreds to thousands of loci, many of which harbor multiple independent peaks, each parsimoniously assumed to be due to the activity of a single causal variant. Fine-mapping of such variants has become a priority and since most associations are located within regulatory regions, it is also assumed that they colocalize with regulatory variants that influence the expression of nearby genes. Here we examine these assumptions by using a moderate throughput expression CROPseq protocol in which Cas9 nuclease is used to induce small insertions and deletions across the credible set of SNPs that may account for expression quantitative trait loci (eQTL) for genes associated with inflammatory bowel disease (IBD). Of the 4,384 SNPs targeted in 88 loci (an average of 50 per locus), 439 were significant and further examined for validation. From these, 98 significantly altered target gene expression in HL-60 myeloid cell line, 74 in induced macrophages from these HL-60 cells, and 78 in induced neutrophils for a total of 201 validated effects (46%), 43 of which were observed in at least two of the cell types. Considering the observed sensitivity and specificity of the controls, we estimate that there are at least 150 true positives per cell type, an average of almost 2.4 for each of the 64 eQTL for which putative causal variants have been fine-mapped. This implies that haplotype effects are likely to explain many of the associations. We also demonstrate that the same approach can be used to investigate the activity of very rare variants in regulatory regions for 89 genes, providing a rapid strategy for establishing clinical relevance of non-coding mutations.

Worldwide study of the taste of bitter medicines and their modifiers

The bitter taste of medicines hinders patient compliance, but not everyone experiences these difficulties because people worldwide differ in their bitterness perception. To better understand how people from diverse ancestries perceive medicines and taste modifiers, 338 adults, European and recent US and Canadian immigrants from Asia, South Asia, and Africa, rated the bitterness intensity of taste solutions on a 100-point generalized visual analog scale and provided a saliva sample for genotyping. The taste solutions were 5 medicines, tenofovir alafenamide (TAF), moxifloxacin, praziquantel, amodiaquine, and propylthiouracil (PROP), and 4 other solutions, TAF mixed with sucralose (sweet, reduces bitterness) or 6-methylflavone (tasteless, reduces bitterness), sucralose alone, and sodium chloride alone. Bitterness ratings differed by ancestry for 2 of the 5 drugs (amodiaquine and PROP) and for TAF mixed with sucralose. Genetic analysis showed that people with variants in 1 bitter receptor variant gene (TAS2R38) reported PROP was more bitter than did those with a different variant (P = 7.6e-19) and that people with either an RIMS2 or a THSD4 genotype found sucralose more bitter than did others (P = 2.6e-8, P = 7.9e-11, respectively). Our findings may help guide the formulation of bad-tasting medicines to meet the needs of those most sensitive to them.

A network-based systems genetics framework identifies pathobiology and drug repurposing in Parkinson's disease

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder. However, current treatments only manage symptoms and lack the ability to slow or prevent disease progression. We utilized a systems genetics approach to identify potential risk genes and repurposable drugs for PD. First, we leveraged non-coding genome-wide association studies (GWAS) loci effects on five types of brain-specific quantitative trait loci (xQTLs, including expression, protein, splicing, methylation and histone acetylation) under the protein-protein interactome (PPI) network. We then prioritized 175 PD likely risk genes (pdRGs), such as SNCA, CTSB, LRRK2, DGKQ, and CD44, which are enriched in druggable targets and differentially expressed genes across multiple human brain-specific cell types. Integrating network proximity-based drug repurposing and patient electronic health record (EHR) data observations, we identified Simvastatin as being significantly associated with reduced incidence of PD (hazard ratio (HR) = 0.91 for fall outcome, 95% confidence interval (CI): 0.87-0.94; HR = 0.88 for dementia outcome, 95% CI: 0.86-0.89) after adjusting for 267 covariates. In summary, our network-based systems genetics framework identifies potential risk genes and repurposable drugs for PD and other neurodegenerative diseases if broadly applied.

A genome-wide association study identifies genetic variants associated with hip pain in the UK Biobank cohort (N = 221,127)

Hip pain is a common musculoskeletal complaint that leads many people to seek medical attention. We conducted a primary genome-wide association study (GWAS) on the hip pain phenotype within the UK Biobank cohort. Sex-stratified GWAS analysis approach was also performed to explore sex specific variants associated with hip pain. We found seven different loci associated with hip pain at GWAS significance level, with the most significant single nucleotide polymorphism (SNP) being rs77641763 within the EXD3 (p value = 2.20 × 10-13). We utilized summary statistics from the FinnGen cohort and a previous GWAS meta-analysis on hip osteoarthritis as replication cohorts. Four loci (rs509345, rs73581564, rs9597759, rs2018384) were replicated with a p value less than 0.05. Sex-stratified GWAS analyses revealed a unique locus within the CUL1 gene (rs4726995, p = 2.56 × 10-9) in males, and three unique loci in females: rs1651359966 on chromosome 7 (p = 1.15 × 10-8), rs552965738 on chromosome 9 (p = 2.72 × 10-8), and rs1978969 on chromosome 13 (p = 2.87 × 10-9). This study has identified seven genetic loci associated with hip pain. Sex-stratified analysis also revealed sex specific variants associated with hip pain in males and females. This study has provided a foundation for advancing research of hip pain and hip osteoarthritis.