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Methylome Analysis of Rare Sinonasal Malignancies: Novel Venues for Clinical Applications

Mladkova, N; Dogan, S; Yaney, A; Snuderl, M; Palmer, J D; Gamez, M E; Bonomi, M; Prevedello, D; Raval, R; Chakravarti, A; Carrau, R; Blakaj, D M
PURPOSE/OBJECTIVE(S): Olfactory neuroblastoma (ONB) and sinonasal undifferentiated carcinoma (SNUC) are rare sinonasal cancers with distinct clinical courses. Methylomic differences between these entities have not been previously explored. The aims of this study were to compare genome-wide methylomes of ONB and SNUC, and to explore candidate tissue of origin of SNUC using a comparative methylomics approach. MATERIALS/METHODS: We included a total of 87 sinonasal malignancy samples. Genome-wide methylome data were obtained with an SNP-based human microarray for 71 ONB-like samples (44 "definitive" ONB samples, 27 ONB-resembling samples) and 10 IDH2-mutatnt SNUC samples. RNA sequencing data for a further 3 ONB and 3 SNUC samples were included. Methylomes were compared between ONB and SNUC samples and to publicly available methylation data for 195 tissue samples representing an array of tumors and normal tissues using R. Strict quality control was performed.
RESULT(S): A total of 41 ONB and 9 SNUC samples passed QC and were included in the final analysis. A total of 89,016 differentially methylated probes had adjusted P-value < 0.01, the majority (90.4%) of which were hypermethylated in SNUC and located predominantly in regulatory regions, likely reflecting IDH2 mutation. The remaining 9.6% were hypomethylated in SNUC samples and were commonly located in intergenic regions. Top differentially methylated regions were GATA3, IGF2, LSP1, NKX6-2 and UNCX. NKX6-2 and UNCX were not expressed in SNUC RNAseq data. Gene set enrichment analysis (GSEA) of differentially hypermethylated CpG-island associated probes with at least 2.5-fold-decrease in SNUC RNA-seq data showed enrichment of EZH2 targets, H3K27 bound genes consistent with previous GSEA in IDH2-mutat sarcomas, in addition to WNT pathway, olfactory transduction, lipid & carbohydrate metabolism and genes pertaining to the nervous system (P < 0.0001). On Pearson's correlation-based analysis, ONB clustered with neuronal samples while SNUC clustered with medulloblastoma (MB) and malignant peripheral nerve sheath tumor (MPNST). On separate correlation, SNUC clustered with T-cell lymphoma, MPNST and MB. On examination of the top 300 differentially methylated probes, SNUC again clustered with MPNST and MB and with a neural crest cluster. On deconvolution analysis, both ONB and SNUC samples showed a predominant T-cell presence, which was significantly higher in SNUC (P < 0.001).
CONCLUSION(S): ONB and SNUC possess distinct methylomes. PRC2 complex dysregulation may represent a key driver of a genome-wide repressive phenotype in IDH2-mutant SNUC samples leading to a dedifferentiated phenotype and may be a potential avenue for targeted therapies in the future. The presence of T-cell infiltration in both tumors represents a potential avenue for exploration of therapeutic checkpoint inhibition. Genome-wide methylomics suggests SNUC may be derived from neuronal tissue and we are currently involved in further transomic approaches to independently validate this hypothesis.
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EMBASE:636626413
ISSN: 1879-355x
CID: 5077782

Magnitude of Mendelian versus complex inheritance of rare disorders

Chakravarti, Aravinda
In medical genetics, the vast majority of patients with a currently known genetic basis harbor a rare deleterious allele explaining its Mendelian inheritance. Increasingly, for these phenotypes, we recognize exceptions to Mendelian expectations from non-penetrance of clinical disease to significant inter-individual variation in clinical manifestations, likely reflecting the actions of additional modifier genes. Despite recent progress, we still remain ignorant about the molecular basis for many rare disorders presumed to be Mendelian. The molecular evidence increasingly suggests a role for multiple genes in some of these cases, but for how many? In this article, I discuss why equating a phenotype as Mendelian or complex may be short-sighted or even erroneous. As we learn more about the functions of the human genome with its genes in networks, we should view the phenotype of an individual patient as arising from his or her total genomic deleterious burden in a set of functionally inter-related genes affecting that phenotype. This can sometimes arise from deleterious allele(s) at a single gene (Mendelian inheritance) creating a specific biochemical deficiency (or excess) but could just as frequently arise from the cumulative effects of multiple disease alleles (complex inheritance) leading to the same biochemical deficiency (or excess).
PMID: 34418293
ISSN: 1552-4833
CID: 5006452

Genome wide pleiotropic analysis to identify novel variants and improve genetic risk score construction [Meeting Abstract]

Zhu, X; Zhu, L; Wang, H; Cooper, R S; Chakravarti, A
Systolic and diastolic blood pressure (S/
EMBASE:636152913
ISSN: 1098-2272
CID: 5024952

Interferon pathway lupus risk alleles modulate risk of death from acute covid-19 [Meeting Abstract]

Nln, I; Ruiz, R F; Muskardin, T W; Tuminello, S; Attur, M; Itturate, E; Petrilli, C; Abramson, S B; Chakravarti, A; Niewold, T
Background/Purpose: Type I interferon (IFN) is critical in our defense against viral infections. Increased type I IFN pathway activation is a genetic risk factor for systemic lupus erythematosus (SLE), and a number of common alleles contribute to the genetic high IFN trait. In this study, we examine whether these common gain-of-function alleles in the type I IFN pathway are associated with protection from mortality in acute COVID-19.
Method(s): We studied IFN pathway SLE risk genes in patients with acute COVID-19 admitted to NYU Langone hospitals (751 European-American and 398 African-American ancestry). The samples were genotyped using low depth sequencing and imputation, and we analyzed data from the following SNPs: IRF5 (rs2004640, rs3807306, rs10488631, rs2280714), IRF7/PHRF (rs1131665, rs4963128), IRF8 (rs17445836, rs12444486), and PRKG1 (rs7897633). Ancestral backgrounds were analyzed separately, and mortality after acute COVID-19 was the primary outcome.
Result(s): We observed specific IRF5 haplotypes that are protective against SLE risk were associated with increased risk of mortality in acute COVID-19 patients in European-American ancestry (OR=3.74, p=0.015). Alleles of PRKG1 were also associated with mortality from COVID-19 in the European-American ancestry cohort (OR=1.80, p=0.0057), and this risk factor was particularly strong in younger patients (OR=29.2, p=0.01 in ages 45-54). IRF8 genotype at rs1244486 was associated with protection from mortality in COVID-19 in African-American subjects aged 65 and older (OR=0.34, p=0.04).
Conclusion(s): We find that a number of type I IFN pathway genes associated with risk of SLE also modulate risk of death during acute COVID-19. Similar to their associations with SLE, these alleles are variably associated with COVID-19 mortality across ancestral backgrounds, suggesting ancestral differences in the genetic regulation of the IFN pathway. These data confirm the critical role of the IFN pathway in our defense against viral infections, and support the idea that some common SLE risk alleles exert protective effects in anti-viral immunity
PMCID:
EMBASE:637275920
ISSN: 2326-5205
CID: 5164662

Sequence-based correction of barcode bias in massively parallel reporter assays

Lee, Dongwon; Kapoor, Ashish; Lee, Changhee; Mudgett, Michael; Beer, Michael A; Chakravarti, Aravinda
Massively parallel reporter assays (MPRAs) are a high-throughput method for evaluating in vitro activities of thousands of candidate cis-regulatory elements (CREs). In these assays, candidate sequences are cloned upstream or downstream from a reporter gene tagged by unique DNA sequences. However, tag sequences may themselves affect reporter gene expression and lead to major potential biases in the measured cis-regulatory activity. Here, we present a sequence-based method for correcting tag-sequence-specific effects and show that our method can significantly reduce this source of variation and improve the identification of functional regulatory variants by MPRAs. We also show that our model captures sequence features associated with post-transcriptional regulation of mRNA. Thus, this new method helps not only to improve detection of regulatory signals in MPRA experiments but also to design better MPRA protocols.
PMID: 34285053
ISSN: 1549-5469
CID: 4979642

Pathogenic alleles in microtubule, secretory granule and extracellular matrix-related genes in familial keratoconus

Shinde, Vishal; Sobreira, Nara; Wohler, Elizabeth S; Maiti, George; Hu, Nan; Silvestri, Giuliana; George, Sonia; Jackson, Jonathan; Chakravarti, Aravinda; Willoughby, Colin E; Chakravarti, Shukti
Keratoconus is a common corneal defect with a complex genetic basis. By whole exome sequencing of affected members from 11 multiplex families of European ancestry, we identified 23 rare, heterozygous, potentially pathogenic variants in 8 genes. These include nonsynonymous single amino acid substitutions in HSPG2, EML6 and CENPF in two families each, and, in NBEAL2, LRP1B, PIK3CG and MRGPRD in three families each; ITGAX had nonsynonymous single amino acid substitutions in two families and an indel with a base substitution producing a nonsense allele in the third family. Only HSPG2, EML6 and CENPF have been associated with ocular phenotypes previously. With the exception of MRGPRD and ITGAX, we detected the transcript and encoded protein of the remaining genes in the cornea and corneal cell cultures. Cultured stromal cells showed cytoplasmic punctate staining of NBEAL2, staining of the fibrillar cytoskeletal network by EML6, while CENPF localized to the basal body of primary cilia. We inhibited the expression of HSPG2, EML6, NBEAL2, and CENPF in stromal cell cultures and assayed for the expression of COL1A1 as a readout of corneal matrix production. An upregulation in COL1A1 after siRNA inhibition indicated their functional link to stromal cell biology. For ITGAX, encoding a leukocyte integrin, we assayed its level in the sera of 3 affected families compared to 10 unrelated controls to detect an increase in all affecteds. Our study identified genes that regulate the cytoskeleton, protein trafficking and secretion, barrier tissue function and response to injury and inflammation, as being relevant to keratoconus.
PMID: 33729517
ISSN: 1460-2083
CID: 4856452

Multi-Ancestry Genome-wide Association Study Accounting for Gene-Psychosocial Factor Interactions Identifies Novel Loci for Blood Pressure Traits

Sun, Daokun; Richard, Melissa; Musani, Solomon K; Sung, Yun Ju; Winkler, Thomas W; Schwander, Karen; Chai, Jin Fang; Guo, Xiuqing; Kilpeläinen, Tuomas O; Vojinovic, Dina; Aschard, Hugues; Bartz, Traci M; Bielak, Lawrence F; Brown, Michael R; Chitrala, Kumaraswamy; Hartwig, Fernando P; Horimoto, Andrea R V R; Liu, Yongmei; Manning, Alisa K; Noordam, Raymond; Smith, Albert V; Harris, Sarah E; Kühnel, Brigitte; Lyytikäinen, Leo-Pekka; Nolte, Ilja M; Rauramaa, Rainer; van der Most, Peter J; Wang, Rujia; Ware, Erin B; Weiss, Stefan; Wen, Wanqing; Yanek, Lisa R; Arking, Dan E; Arnett, Donna K; Barac, Ana; Boerwinkle, Eric; Broeckel, Ulrich; Chakravarti, Aravinda; Chen, Yii-Der Ida; Cupples, L Adrienne; Davigulus, Martha L; de Las Fuentes, Lisa; de Mutsert, Renée; de Vries, Paul S; Delaney, Joseph A C; Roux, Ana V Diez; Dörr, Marcus; Faul, Jessica D; Fretts, Amanda M; Gallo, Linda C; Grabe, Hans Jörgen; Gu, C Charles; Harris, Tamara B; Hartman, Catharina C A; Heikkinen, Sami; Ikram, M Arfan; Isasi, Carmen; Johnson, W Craig; Jonas, Jost Bruno; Kaplan, Robert C; Komulainen, Pirjo; Krieger, Jose E; Levy, Daniel; Liu, Jianjun; Lohman, Kurt; Luik, Annemarie I; Martin, Lisa W; Meitinger, Thomas; Milaneschi, Yuri; O'Connell, Jeff R; Palmas, Walter R; Peters, Annette; Peyser, Patricia A; Pulkki-RÃ¥back, Laura; Raffel, Leslie J; Reiner, Alex P; Rice, Kenneth; Robinson, Jennifer G; Rosendaal, Frits R; Schmidt, Carsten Oliver; Schreiner, Pamela J; Schwettmann, Lars; Shikany, James M; Shu, Xiao-Ou; Sidney, Stephen; Sims, Mario; Smith, Jennifer A; Sotoodehnia, Nona; Strauch, Konstantin; Tai, E Shyong; Taylor, Kent; Uitterlinden, André G; van Duijn, Cornelia M; Waldenberger, Melanie; Wee, Hwee-Lin; Wei, Wen-Bin; Wilson, Gregory; Xuan, Deng; Yao, Jie; Zeng, Donglin; Zhao, Wei; Zhu, Xiaofeng; Zonderman, Alan B; Becker, Diane M; Deary, Ian J; Gieger, Christian; Lakka, Timo A; Lehtimäki, Terho; North, Kari E; Oldehinkel, Albertine J; Penninx, Brenda W J H; Snieder, Harold; Wang, Ya-Xing; Weir, David R; Zheng, Wei; Evans, Michele K; Gauderman, W James; Gudnason, Vilmundur; Horta, Bernardo L; Liu, Ching-Ti; Mook-Kanamori, Dennis O; Morrison, Alanna C; Pereira, Alexandre C; Psaty, Bruce M; Amin, Najaf; Fox, Ervin R; Kooperberg, Charles; Sim, Xueling; Bierut, Laura; Rotter, Jerome I; Kardia, Sharon L R; Franceschini, Nora; Rao, Dabeeru C; Fornage, Myriam
Psychological and social factors are known to influence blood pressure (BP) and risk of hypertension and associated cardiovascular diseases. To identify novel BP loci, we carried out genome-wide association meta-analyses of systolic, diastolic, pulse, and mean arterial BP taking into account the interaction effects of genetic variants with three psychosocial factors: depressive symptoms, anxiety symptoms, and social support. Analyses were performed using a two-stage design in a sample of up to 128,894 adults from 5 ancestry groups. In the combined meta-analyses of Stages 1 and 2, we identified 59 loci (p value <5e-8), including nine novel BP loci. The novel associations were observed mostly with pulse pressure, with fewer observed with mean arterial pressure. Five novel loci were identified in African ancestry, and all but one showed patterns of interaction with at least one psychosocial factor. Functional annotation of the novel loci supports a major role for genes implicated in the immune response (PLCL2), synaptic function and neurotransmission (LIN7A, PFIA2), as well as genes previously implicated in neuropsychiatric or stress-related disorders (FSTL5, CHODL). These findings underscore the importance of considering psychological and social factors in gene discovery for BP, especially in non-European populations.
PMCID:8562625
PMID: 34734193
ISSN: 2666-2477
CID: 5038282

The road ahead in genetics and genomics

McGuire, Amy L; Gabriel, Stacey; Tishkoff, Sarah A; Wonkam, Ambroise; Chakravarti, Aravinda; Furlong, Eileen E M; Treutlein, Barbara; Meissner, Alexander; Chang, Howard Y; López-Bigas, Núria; Segal, Eran; Kim, Jin-Soo
In celebration of the 20th anniversary of Nature Reviews Genetics, we asked 12 leading researchers to reflect on the key challenges and opportunities faced by the field of genetics and genomics. Keeping their particular research area in mind, they take stock of the current state of play and emphasize the work that remains to be done over the next few years so that, ultimately, the benefits of genetic and genomic research can be felt by everyone.
PMCID:7444682
PMID: 32839576
ISSN: 1471-0064
CID: 4576222

MicroRNA-4516-mediated regulation of MAPK10 relies on 3' UTR cis-acting variants and contributes to the altered risk of Hirschsprung disease

Wang, Yang; Jiang, Qian; Chakravarti, Aravinda; Cai, Hao; Xu, Ze; Wu, Wenjie; Gu, Beilin; Li, Long; Cai, Wei
BACKGROUND:in HSCR and how they contribute to the pathogenesis of HSCR. METHODS:-acting elements in MAPK10 on miR-4516-mediated modulation and cell migration process. RESULTS:rescued the effect of miR-4516 on the migration of human neural cells. CONCLUSION/CONCLUSIONS:- and posttranscriptional modulation for HSCR pathogenesis.
PMID: 32066630
ISSN: 1468-6244
CID: 4313082

Analysis of putative cis-regulatory elements regulating blood pressure variation

Nandakumar, Priyanka; Lee, Dongwon; Hoffmann, Thomas J; Ehret, Georg B; Arking, Dan; Ranatunga, Dilrini; Li, Man; Grove, Megan L; Boerwinkle, Eric; Schaefer, Catherine; Kwok, Pui-Yan; Iribarren, Carlos; Risch, Neil; Chakravarti, Aravinda
Hundreds of loci have been associated with blood pressure traits from many genome-wide association studies. We identified an enrichment of these loci in aorta and tibial artery expression quantitative trait loci in our previous work in ~ 100 000 Genetic Epidemiology Research on Aging (GERA) study participants. In the present study, we sought to fine-map known loci and identify novel genes by determining putative regulatory regions for these and other tissues relevant to blood pressure. We constructed maps of putative cis-regulatory elements using publicly available open chromatin data for the heart, aorta and tibial arteries, and multiple kidney cell types. Variants within these regions may be evaluated quantitatively for their tissue- or cell-type-specific regulatory impact using deltaSVM functional scores, as described in our previous work. We aggregate variants within these putative cis-regulatory elements within 50Kb of the start or end of 'expressed' genes in these tissues or cell types using public expression data, and use deltaSVM scores as weights in the group-wise sequence kernel association test (SKAT) to identify candidates. We test for association with both blood pressure traits and expression within these tissues or cell types of interest, and identify the candidates MTHFR, C10orf32, CSK, NOV, ULK4, SDCCAG8, SCAMP5, RPP25, HDGFRP3, VPS37B, and PPCDC. Additionally, we examined two known QT interval genes, SCN5A and NOS1AP, in the Atherosclerosis Risk in Communities Study (ARIC), as a positive control, and observed the expected heart-specific effect. Thus, our method identifies variants and genes for further functional testing using tissue- or cell-type-specific putative regulatory information.
PMID: 32436959
ISSN: 1460-2083
CID: 4446962