Browsing by Author "Chuang, Ling-Shiang"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Functional variants in the LRRK2 gene confer shared effects on risk for Crohn's disease and Parkinson's disease
    (American Association for the Advancement of Science, 2018-01-10) Hui, Ken Y.; Fernandez-Hernandez, Heriberto; Hu, Jianzhong; Schaffner, Adam; Pankratz, Nathan; Hsu, Nai-Yun; Chuang, Ling-Shiang; Carmi, Shai; Villaverde, Nicole; Li, Xianting; Rivas, Manual; Levine, Adam P.; Bao, Xiuliang; Labrias, Philippe R.; Haritunians, Talin; Ruane, Darren; Gettler, Kyle; Chen, Ernie; Li, Dalin; Schiff, Elena R.; Pontikos, Nikolas; Barzilai, Nir; Brant, Steven R.; Bressman, Susan; Cheifetz, Adam S.; Clark, Lorraine N.; Daly, Mark J.; Desnick, Robert J.; Duerr, Richard H.; Katz, Seymour; Lencz, Todd; Myers, Richard H.; Ostrer, Harry; Ozelius, Laurie; Payami, Haydeh; Peter, Yakov; Rioux, John D.; Segal, Anthony W.; Scott, William K.; Silverberg, Mark S.; Vance, Jeffery M.; Ubarretxena-Belandia, Iban; Foroud, Tatiana; Atzmon, Gil; Pe’er, Itsik; Ioannou, Yiannis; McGovern, Dermot P.B.; Yue, Zhenyu; Schadt, Eric E.; Cho, Judy H.; Peter, Inga; Medical and Molecular Genetics, School of Medicine
    Crohn's disease (CD), a form of inflammatory bowel disease, has a higher prevalence in Ashkenazi Jewish than in non-Jewish European populations. To define the role of nonsynonymous mutations, we performed exome sequencing of Ashkenazi Jewish patients with CD, followed by array-based genotyping and association analysis in 2066 CD cases and 3633 healthy controls. We detected association signals in the LRRK2 gene that conferred risk for CD (N2081D variant, P = 9.5 × 10-10) or protection from CD (N551K variant, tagging R1398H-associated haplotype, P = 3.3 × 10-8). These variants affected CD age of onset, disease location, LRRK2 activity, and autophagy. Bayesian network analysis of CD patient intestinal tissue further implicated LRRK2 in CD pathogenesis. Analysis of the extended LRRK2 locus in 24,570 CD cases, patients with Parkinson's disease (PD), and healthy controls revealed extensive pleiotropy, with shared genetic effects between CD and PD in both Ashkenazi Jewish and non-Jewish cohorts. The LRRK2 N2081D CD risk allele is located in the same kinase domain as G2019S, a mutation that is the major genetic cause of familial and sporadic PD. Like the G2019S mutation, the N2081D variant was associated with increased kinase activity, whereas neither N551K nor R1398H variants on the protective haplotype altered kinase activity. We also confirmed that R1398H, but not N551K, increased guanosine triphosphate binding and hydrolyzing enzyme (GTPase) activity, thereby deactivating LRRK2. The presence of shared LRRK2 alleles in CD and PD provides refined insight into disease mechanisms and may have major implications for the treatment of these two seemingly unrelated diseases.
  • Thumbnail Image
    Item
    Stratification of risk of progression to colectomy in ulcerative colitis via measured and predicted gene expression
    (Elsevier, 2021) Mo, Angela; Nagpal, Sini; Gettler, Kyle; Haritunians, Talin; Giri, Mamta; Haberman, Yael; Karns, Rebekah; Prince, Jarod; Arafat, Dalia; Hsu, Nai-Yun; Chuang, Ling-Shiang; Argmann, Carmen; Kasarskis, Andrew; Suarez-Farinas, Mayte; Gotman, Nathan; Mengesha, Emebet; Venkateswaran, Suresh; Rufo, Paul A.; Baker, Susan S.; Sauer, Cary G.; Markowitz, James; Pfefferkorn, Marian D.; Rosh, Joel R.; Boyle, Brendan M.; Mack, David R.; Baldassano, Robert N.; Shah, Sapana; LeLeiko, Neal S.; Heyman, Melvin B.; Griffiths, Anne M.; Patel, Ashish S.; Noe, Joshua D.; Davis Thomas, Sonia; Aronow, Bruce J.; Walters, Thomas D.; McGovern, Dermot P.B.; Hyams, Jeffrey S.; Kugathasan, Subra; Cho, Judy H.; Denson, Lee A.; Gibson, Greg; Pediatrics, School of Medicine
    An important goal of clinical genomics is to be able to estimate the risk of adverse disease outcomes. Between 5% and 10% of individuals with ulcerative colitis (UC) require colectomy within 5 years of diagnosis, but polygenic risk scores (PRSs) utilizing findings from genome-wide association studies (GWASs) are unable to provide meaningful prediction of this adverse status. By contrast, in Crohn disease, gene expression profiling of GWAS-significant genes does provide some stratification of risk of progression to complicated disease in the form of a transcriptional risk score (TRS). Here, we demonstrate that a measured TRS based on bulk rectal gene expression in the PROTECT inception cohort study has a positive predictive value approaching 50% for colectomy. Single-cell profiling demonstrates that the genes are active in multiple diverse cell types from both the epithelial and immune compartments. Expression quantitative trait locus (QTL) analysis identifies genes with differential effects at baseline and week 52 follow-up, but for the most part, differential expression associated with colectomy risk is independent of local genetic regulation. Nevertheless, a predicted polygenic transcriptional risk score (PPTRS) derived by summation of transcriptome-wide association study (TWAS) effects identifies UC-affected individuals at 5-fold elevated risk of colectomy with data from the UK Biobank population cohort studies, independently replicated in an NIDDK-IBDGC dataset. Prediction of gene expression from relatively small transcriptome datasets can thus be used in conjunction with TWASs for stratification of risk of disease complications.