Browsing by Author "Xuei, Xiaoling"
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Item 38766 Massively Parallel Reporter Assay Reveals Functional Impact of 3™-UTR SNPs Associated with Neurological and Psychiatric Disorders(Cambridge University Press, 2021) Chen, Andy B.; Thapa, Kriti; Gao, Hongyu; Reiter, Jill L.; Zhang, Junjie; Xuei, Xiaoling; Gu, Hongmei; Wang, Yue; Edenberg, Howard J.; Liu, Yunlong; Medical and Molecular Genetics, School of MedicineABSTRACT IMPACT: Screening the effect of thousands of non-coding genetic variants will help identify variants important in the etiology of diseases OBJECTIVES/GOALS: Massively parallel reporter assays (MPRAs) can experimentally evaluate the impact of genetic variants on gene expression. In this study, our objective was to systematically evaluate the functional activity of 3’-UTR SNPs associated with neurological disorders and use those results to help understand their contributions to disease etiology. METHODS/STUDY POPULATION: To choose variants to evaluate with the MPRA, we first gathered SNPs from the GWAS Catalog that were associated with any neurological disorder trait with p-value < 10-5. For each SNP, we identified the region that was in linkage disequilibrium (r2 > 0.8) and retrieved all the common 3’-UTR SNPs (allele-frequency > 0.05) within that region. We used an MPRA to measure the impact of these 3’-UTR variants in SH-SY5Y neuroblastoma cells and a microglial cell line. These results were then used to train a deep-learning model to predict the impact of variants and identify features that contribute to the predictions. RESULTS/ANTICIPATED RESULTS: Of the 13,515 3’-UTR SNPs tested, 400 and 657 significantly impacted gene expression in SH-SY5Y and microglia, respectively. Of the 84 SNPs significantly impacted in both cells, the direction of impact was the same in 81. The direction of eQTL in GTEx tissues agreed with the assay SNP effect in SH-SY5Y cells but not microglial cells. The deep-learning model predicted sequence activity level correlated with the experimental activity level (Spearman’s corr = 0.45). The deep-learning model identified several predictive motifs similar to motifs of RNA-binding proteins. DISCUSSION/SIGNIFICANCE OF FINDINGS: This study demonstrates that MPRAs can be used to evaluate the effect of non-coding variants, and the results can be used to train a machine learning model and interpret its predictions. Together, these can help identify causal variants and further understand the etiology of diseases.Item 5. Collaborative Study on the Genetics of Alcoholism: Functional genomics(Wiley, 2023) Gameiro-Ros, Isabel; Popova, Dina; Prytkova, Iya; Pang, Zhiping P.; Liu, Yunlong; Dick, Danielle; Bucholz, Kathleen K.; Agrawal, Arpana; Porjesz, Bernice; Goate, Alison M.; Xuei, Xiaoling; Kamarajan, Chella; COGA Collaborators; Tischfield, Jay A.; Edenberg, Howard J.; Slesinger, Paul A.; Hart, Ronald P.; Medical and Molecular Genetics, School of MedicineAlcohol Use Disorder is a complex genetic disorder, involving genetic, neural, and environmental factors, and their interactions. The Collaborative Study on the Genetics of Alcoholism (COGA) has been investigating these factors and identified putative alcohol use disorder risk genes through genome-wide association studies. In this review, we describe advances made by COGA in elucidating the functional changes induced by alcohol use disorder risk genes using multimodal approaches with human cell lines and brain tissue. These studies involve investigating gene regulation in lymphoblastoid cells from COGA participants and in post-mortem brain tissues. High throughput reporter assays are being used to identify single nucleotide polymorphisms in which alternate alleles differ in driving gene expression. Specific single nucleotide polymorphisms (both coding or noncoding) have been modeled using induced pluripotent stem cells derived from COGA participants to evaluate the effects of genetic variants on transcriptomics, neuronal excitability, synaptic physiology, and the response to ethanol in human neurons from individuals with and without alcohol use disorder. We provide a perspective on future studies, such as using polygenic risk scores and populations of induced pluripotent stem cell-derived neurons to identify signaling pathways related with responses to alcohol. Starting with genes or loci associated with alcohol use disorder, COGA has demonstrated that integration of multimodal data within COGA participants and functional studies can reveal mechanisms linking genomic variants with alcohol use disorder, and potential targets for future treatments.Item A genome wide association study of alcohol dependence symptom counts in extended pedigrees identifies C15orf53(Springer Nature, 2013) Wang, Jen-Chyong; Foroud, Tatiana; Hinrichs, Anthony L.; Le, Nhung X. H.; Bertelsen, Sarah; Budde, John P.; Harari, Oscar; Koller, Daniel L.; Wetherill, Leah; Agrawal, Arpana; Almasy, Laura; Brooks, Andrew I.; Bucholz, Kathleen; Dick, Danielle; Hesselbrock, Victor; Johnson, Eric O.; Kang, Sun; Kapoor, Manav; Kramer, John; Kuperman, Samuel; Madden, Pamela A. F.; Manz, Niklas; Martin, Nicholas G.; McClintick, Jeanette N.; Montgomery, Grant W.; Nurnberger, John I., Jr.; Rangaswamy, Madhavi; Rice, John; Schuckit, Marc; Tischfield, Jay A.; Whitfield, John B.; Xuei, Xiaoling; Porjesz, Bernice; Heath, Andrew C.; Edenberg, Howard J.; Bierut, Laura J.; Goate, Alison M.; Medical and Molecular Genetics, School of MedicineSeveral studies have identified genes associated with alcohol-use disorders (AUDs), but the variation in each of these genes explains only a small portion of the genetic vulnerability. The goal of the present study was to perform a genome-wide association study (GWAS) in extended families from the Collaborative Study on the Genetics of Alcoholism to identify novel genes affecting risk for alcohol dependence (AD). To maximize the power of the extended family design, we used a quantitative endophenotype, measured in all individuals: number of alcohol-dependence symptoms endorsed (symptom count (SC)). Secondary analyses were performed to determine if the single nucleotide polymorphisms (SNPs) associated with SC were also associated with the dichotomous phenotype, DSM-IV AD. This family-based GWAS identified SNPs in C15orf53 that are strongly associated with DSM-IV alcohol-dependence symptom counts (P=4.5 × 10(-8), inflation-corrected P=9.4 × 10(-7)). Results with DSM-IV AD in the regions of interest support our findings with SC, although the associations were less significant. Attempted replications of the most promising association results were conducted in two independent samples: nonoverlapping subjects from the Study of Addiction: Genes and Environment (SAGE) and the Australian Twin Family Study of AUDs (OZALC). Nominal association of C15orf53 with SC was observed in SAGE. The variant that showed strongest association with SC, rs12912251 and its highly correlated variants (D'=1, r(2) 0.95), have previously been associated with risk for bipolar disorder.Item A metabolic shift to the serine pathway induced by lipids fosters epigenetic reprogramming in nontransformed breast cells(American Association for the Advancement of Science, 2025) Eduardo, Mariana Bustamante; Cottone, Gannon; McCloskey, Curtis W.; Liu, Shiyu; Palma, Flavio R.; Zappia, Maria Paula; Islam, Abul B. M. M. K.; Gao, Peng; Setya, Joel; Dennis, Saya; Gao, Hongyu; Zhang, Qian; Xuei, Xiaoling; Luo, Yuan; Locasale, Jason; Bonini, Marcelo G.; Khokha, Rama; Frolov, Maxim V.; Benevolenskaya, Elizaveta V.; Chandel, Navdeep S.; Khan, Seema A.; Clare, Susan E.; Medical and Molecular Genetics, School of MedicineLipid metabolism and the serine, one-carbon, glycine (SOG) and methionine pathways are independently and significantly correlated with estrogen receptor-negative breast cancer (ERneg BC). Here, we propose a link between lipid metabolism and ERneg BC through phosphoglycerate dehydrogenase (PHGDH), the rate-limiting enzyme in the de novo serine pathway. We demonstrate that the metabolism of the paradigmatic medium-chain fatty acid octanoic acid leads to a metabolic shift toward the SOG and methionine pathways. PHGDH plays a role in both the forward direction, contributing to the production of S-adenosylmethionine, and the reverse direction, generating the oncometabolite 2-hydroxyglutarate, leading to epigenomic reprogramming and phenotypic plasticity. The methionine cycle is closely linked to the transsulfuration pathway. Consequently, we observe that the shift increases the antioxidant glutathione, which mitigates reactive oxygen species (ROS), enabling survival of a subset of cells that have undergone DNA damage. These metabolic changes contribute to several hallmarks of cancer.Item Adaptation of Subjective Responses to Alcohol is Affected by an Interaction of GABRA2 Genotype and Recent Drinking(Wiley Blackwell (Blackwell Publishing), 2015-07) Kosobud, Ann E. K.; Wetherill, Leah; Plawecki, Martin H.; Kareken, David A.; Liang, Tiebing; Nurnberger, John L.; Windisch, Kyle; Xuei, Xiaoling; Edenberg, Howard J.; Foroud, Tatiana M.; O’Connor, Sean J.; Department of Psychiatry, IU School of MedicineBACKGROUND: Subjective perceptions of alcohol intoxication are associated with altered risk for alcohol abuse and dependence. Acute adaptation of these perceptions may influence such risk and may involve genes associated with pleasant perceptions or the relief of anxiety. This study assessed the effect of variation in the GABAA receptor genes GABRG1 and GABRA2 and recent drinking history on the acute adaptation of subjective responses to alcohol. METHODS: One hundred and thirty-two nondependent moderate to heavy drinkers, aged 21 to 27, participated in 2 single-blind, counterbalanced sessions, approximately 1 week apart. One session was an intravenous alcohol "clamp," during which breath alcohol concentration was held steady at 60 mg/dl (60 mg%) for 3 hours, and the other an identical session using saline infusion. Subjective perceptions of Intoxication, Enjoyment, Stimulation, Relaxation, Anxiety, Tiredness, and Estimated Number of Drinks were acquired before (baseline), and during the first and final 45 minutes of the clamp. A placebo-adjusted index of the subject's acute adaptation to alcohol was calculated for each of the 7 subjective measures and used in a principal component analysis to create a single aggregate estimate for each subject's adaptive response to alcohol. Analysis of covariance tested whether GABRA2 and GABRG1 single nucleotide polymorphism (SNP) genotypes, gender, placebo session, family history of alcoholism, recent drinking history, and the genotype × recent drinking history interaction significantly predicted the adaptive response. RESULTS: Recent drinking history (p = 0.01), and recent drinking history × genotype interaction (p = 0.01) were significantly associated with acute adaptation of the subjective responses to alcohol for the GABRA2 SNP rs279858. CONCLUSIONS: Higher recent drinking was found to be associated with reduced acute tolerance to positive, stimulating effects of alcohol in carriers of the rs279858 risk allele. We postulate that the GABRA2 effect on alcohol dependence may, in part, be due to its effect on subjective responses to alcohol.Item Alcohol reverses the effects of KCNJ6 (GIRK2) noncoding variants on excitability of human glutamatergic neurons(Springer Nature, 2023) Popova, Dina; Gameiro-Ros, Isabel; Youssef, Mark M.; Zalamea, Petronio; Morris, Ayeshia D.; Prytkova, Iya; Jadali, Azadeh; Kwan, Kelvin Y.; Kamarajan, Chella; Salvatore, Jessica E.; Xuei, Xiaoling; Chorlian, David B.; Porjesz, Bernice; Kuperman, Samuel; Dick, Danielle M.; Goate, Alison; Edenberg, Howard J.; Tischfield, Jay A.; Pang, Zhiping P.; Slesinger, Paul A.; Hart, Ronald P.; Medical and Molecular Genetics, School of MedicineSynonymous and noncoding single nucleotide polymorphisms (SNPs) in the KCNJ6 gene, encoding G protein-gated inwardly rectifying potassium channel subunit 2 (GIRK2), have been linked with increased electroencephalographic frontal theta event-related oscillations (ERO) in subjects diagnosed with alcohol use disorder (AUD). To identify molecular and cellular mechanisms while retaining the appropriate genetic background, we generated induced excitatory glutamatergic neurons (iN) from iPSCs derived from four AUD-diagnosed subjects with KCNJ6 variants ("Affected: AF") and four control subjects without variants ("Unaffected: UN"). Neurons were analyzed for changes in gene expression, morphology, excitability and physiological properties. Single-cell RNA sequencing suggests that KCNJ6 AF variant neurons have altered patterns of synaptic transmission and cell projection morphogenesis. Results confirm that AF neurons express lower levels of GIRK2, have greater neurite area, and elevated excitability. Interestingly, exposure to intoxicating concentrations of ethanol induces GIRK2 expression and reverses functional effects in AF neurons. Ectopic overexpression of GIRK2 alone mimics the effect of ethanol to normalize induced excitability. We conclude that KCNJ6 variants decrease GIRK2 expression and increase excitability and that this effect can be minimized or reduced with ethanol.Item Allele-specific expression and high-throughput reporter assay reveal functional genetic variants associated with alcohol use disorders(Springer Nature, 2021-04) Rao, Xi; Thapa, Kriti S.; Chen, Andy B.; Lin, Hai; Gao, Hongyu; Reiter, Jill L.; Hargreaves, Katherine A.; Ipe, Joseph; Lai, Dongbing; Xuei, Xiaoling; Wang, Yue; Gu, Hongmei; Kapoor, Manav; Farris, Sean P.; Tischfield, Jay; Foroud, Tatiana; Goate, Alison M.; Skaar, Todd C.; Mayfield, R. Dayne; Edenberg, Howard J.; Liu, Yunlong; Medical and Molecular Genetics, School of MedicineGenome-wide association studies (GWAS) of complex traits, such as alcohol use disorders (AUD), usually identify variants in non-coding regions and cannot by themselves distinguish whether the associated variants are functional or in linkage disequilibrium with the functional variants. Transcriptome studies can identify genes whose expression differs between alcoholics and controls. To test which variants associated with AUD may cause expression differences, we integrated data from deep RNA-seq and GWAS of four postmortem brain regions from 30 subjects with AUD and 30 controls to analyze allele-specific expression (ASE). We identified 88 genes with differential ASE in subjects with AUD compared to controls. Next, to test one potential mechanism contributing to the differential ASE, we analyzed single nucleotide polymorphisms (SNPs) in the 3′ untranslated regions (3′UTR) of these genes. Of the 88 genes with differential ASE, 61 genes contained 437 SNPs in the 3′UTR with at least one heterozygote among the subjects studied. Using a modified PASSPORT-seq (parallel assessment of polymorphisms in miRNA target-sites by sequencing) assay, we identified 25 SNPs that affected RNA levels in a consistent manner in two neuroblastoma cell lines, SH-SY5Y and SK-N-BE(2). Many of these SNPs are in binding sites of miRNAs and RNA-binding proteins, indicating that these SNPs are likely causal variants of AUD-associated differential ASE. In sum, we demonstrate that a combination of computational and experimental approaches provides a powerful strategy to uncover functionally relevant variants associated with the risk for AUD.Item Allele-specific expression and high-throughput reporter assay reveal functional genetic variants associated with alcohol use disorders.(Springer, 2021-04) Rao, Xi; Thapa, Kriti S.; Chen, Andy B.; Lin, Hai; Gao, Hongyu; Reiter, Jill L.; Hargreaves, Katherine A.; Ipe, Joseph; Lai, Dongbing; Xuei, Xiaoling; Wang, Yue; Gu, Hongmei; Kapoor, Manav; Farris, Sean P.; Tischfield, Jay; Foroud, Tatiana; Goate, Alison M.; Skaar, Todd C.; Mayfield, R. Dayne; Edenberg, Howard J.; Liu, YunlongGenome-wide association studies (GWAS) of complex traits, such as alcohol use disorders (AUD), usually identify variants in non-coding regions and cannot by themselves distinguish whether the associated variants are functional or in linkage disequilibrium with the functional variants. Transcriptome studies can identify genes whose expression differs between alcoholics and controls. To test which variants associated with AUD may cause expression differences, we integrated data from deep RNA-seq and GWAS of four postmortem brain regions from 30 subjects with AUD and 30 controls to analyze allele-specific expression (ASE). We identified 88 genes with differential ASE in subjects with AUD compared to controls. Next, to test one potential mechanism contributing to the differential ASE, we analyzed single nucleotide polymorphisms (SNPs) in the 3' untranslated regions (3'UTR) of these genes. Of the 88 genes with differential ASE, 61 genes contained 437 SNPs in the 3'UTR with at least one heterozygote among the subjects studied. Using a modified PASSPORT-seq (parallel assessment of polymorphisms in miRNA target-sites by sequencing) assay, we identified 25 SNPs that affected RNA levels in a consistent manner in two neuroblastoma cell lines, SH-SY5Y and SK-N-BE(2). Many of these SNPs are in binding sites of miRNAs and RNA-binding proteins, indicating that these SNPs are likely causal variants of AUD-associated differential ASE. In sum, we demonstrate that a combination of computational and experimental approaches provides a powerful strategy to uncover functionally relevant variants associated with the risk for AUD.Item Angiotensin-related genetic determinants of cardiovascular disease in patients undergoing hemodialysis(Oxford University Press, 2019-11) Moe, Sharon M.; Long, Jin; Schwantes-An, Tae-Hwi Linus; Decker, Brian S.; Wetherill, Leah; Edenberg, Howard J.; Xuei, Xiaoling; Vatta, Matteo; Foroud, Tatiana M.; Chertow, Glenn M.; Medicine, School of MedicineBACKGROUND: Cardiovascular mortality in patients receiving dialysis remains unacceptably high, with unexplained ancestry differences suggesting a genetic component. METHODS: We analyzed DNA samples from 37% of subjects enrolled in the EValuation Of Cinacalcet Hydrochloride (HCl) Therapy to Lower CardioVascular Events (EVOLVE) trial, a randomized trial conducted in patients receiving hemodialysis with secondary hyperparathyroidism, comparing cinacalcet to placebo on a background of usual care. DNA was analyzed for single-nucleotide polymorphisms (SNPs) in the genes encoding the angiotensin-converting enzyme receptor type I (AGTR1) and angiotensin-converting enzyme (ACE). Survival analyses were conducted separately in European Ancestry (EA) and African Ancestry (AfAn) due to known differences in cardiovascular events, minor alleles for the same variant and the frequency of minor alleles. Our primary determination was a meta-analysis across both races. RESULTS: Meta-analysis showed significant associations between rs5186 in AGTR1 and increased rates by 25-34% for the primary endpoint (composite of death or nonfatal myocardial infarction, hospitalization for unstable angina, heart failure or peripheral vascular event), all-cause mortality, cardiovascular mortality and heart failure; all P < 0.001. Three correlated SNPs in ACE were associated with lower rates of sudden cardiac death (SCD) in EA samples. One ACE SNP, rs4318, only found in the AfAn samples, was associated with a lower rate of SCD in the AfAn samples. CONCLUSIONS: The C allele in rs5186 in AGTR1 was associated with higher rates of death and major cardiovascular events in a meta-analysis of EA and AfAn patients with end-stage kidney disease. SNPs in ACE were associated with SCD.Item Aspergillus versicolor Inhalation Triggers Neuroimmune, Glial, and Neuropeptide Transcriptional Changes(Sage, 2021) Ladd, Thatcher B.; Johnson, James A., Jr.; Mumaw, Christen L.; Greve, Hendrik J.; Xuei, Xiaoling; Simpson, Ed; Barnes, Mark A.; Green, Brett J.; Croston, Tara L.; Ahmed, Chandrama; Lemons, Angela; Beezhold, Donald H.; Block, Michelle L.; Medical and Molecular Genetics, School of MedicineIncreasing evidence associates indoor fungal exposure with deleterious central nervous system (CNS) health, such as cognitive and emotional deficits in children and adults, but the specific mechanisms by which it might impact the brain are poorly understood. Mice were exposed to filtered air, heat-inactivated Aspergillus versicolor (3 × 105 spores), or viable A. versicolor (3 × 105 spores) via nose-only inhalation exposure 2 times per week for 1, 2, or 4 weeks. Analysis of cortex, midbrain, olfactory bulb, and cerebellum tissue from mice exposed to viable A. versicolor spores for 1, 2, and 4 weeks revealed significantly elevated pro-inflammatory (Tnf and Il1b) and glial activity (Gdnf and Cxc3r1) gene expression in several brain regions when compared to filtered air control, with the most consistent and pronounced neuroimmune response 48H following the 4-week exposure in the midbrain and frontal lobe. Bulk RNA-seq analysis of the midbrain tissue confirmed that 4 weeks of A. versicolor exposure resulted in significant transcriptional enrichment of several biological pathways compared to the filtered air control, including neuroinflammation, glial cell activation, and regulation of postsynaptic organization. Upregulation of Drd1, Penk, and Pdyn mRNA expression was confirmed in the 4-week A. versicolor exposed midbrain tissue, highlighting that gene expression important for neurotransmission was affected by repeated A. versicolor inhalation exposure. Taken together, these findings indicate that the brain can detect and respond to A. versicolor inhalation exposure with changes in neuroimmune and neurotransmission gene expression, providing much needed insight into how inhaled fungal exposures can affect CNS responses and regulate neuroimmune homeostasis.