Sudha K. Iyengar, PhD

Professor and Vice Chair for Research
Department of Population and Quantitative Health Sciences
School of Medicine
Department of Genetics and Genome Sciences
School of Medicine
Department of Ophthalmology and Visual Sciences
School of Medicine
Cleveland Institute for Computational Biology
School of Medicine
Cancer Genomics and Epigenomics Program
Case Comprehensive Cancer Center

Dr. Sudha K. Iyengar is an internationally recognized genetic epidemiologist focused in the study of the genetics of vision, renal disease, and speech-sound disorder. She currently directs a multifaceted laboratory that bridges both bench and computational research. Her laboratory is responsible for identification of genes for many diseases, including novel genes for age-related macular degeneration (AMD), age-related cataract and Fuchs Endothelial Corneal Dystrophy (FECD).  She has a long track record in directing research that requires the management of large datasets and analysis with high density genome-wide linkage, genome-wide association, methylation analysis and next-generation sequencing type data, including workflows and quality control for exome sequencing, RNA-seq and ChIP seq. Four concurrent funded efforts in Dr. Iyengar’s portfolio include mapping the genetic architecture of diabetic retinopathy in South Asia, identifying genes, hormones, and behavioral deficits that predict speech-sound disorder, ocular clinical conditions (e.g. AMD) and the Million Veteran Program, and a project to perform a genome-wide association study for microbial keratitis leading to corneal ulcers.

Teaching Information

Courses Taught

Principles of BioMedicine
Principles of Genetic Epidemiology
Genetic Epidemiology
Research in Genetics

Research Information

Research Projects

Her laboratory is responsible for identification of genes for many different diseases, most recently for Age-Related Macular Degeneration (AMD) and Fuchs’ Endothelial Corneal Dystrophy (FECD). Her research shows that these diseases are not necessarily caused by changes in a single gene, but by common and rare variation in many genes acting in conjunction. Finding these changes requires processing of information from many sources, including detailed family and medical histories of participants, using high-dimensional arrays or direct sequencing to capture information on the genome, harvesting tissue from affected individuals followed by functional genomic analysis to comprehend which genes show aberrant profiles, all of which her laboratory has accomplished. Having found novel genes for AMD and FECD, she has expanded her work and is now trying to understand why these changes lead to disease. Thus, the scope of her research is broad, multidisciplinary, and frequently collaborative with other disciplines.

Findings from her laboratory are described in over 120 primary research papers, many of which are published in leading scientific journals. Dr. Iyengar’s research is supported via strong NIH grant funding, with her being the Principal Investigator of two consortia, the Family Investigation of Nephropathy and Diabetes Study, and the Fuchs’ Endothelial Corneal Dystrophy Multicenter Genetics Study. Dr. Iyengar is a mentor to several junior faculty at Case, and many of her former graduate students and post-doctoral fellows are now faculty with NIH funding. To summarize her career so far, she is a well established genetic epidemiologist, who has lead the fields of the genetics of vision, renal and speech-sound disorder at Case Western Reserve University and beyond.

Professional Memberships

American Society of Human Genetics, Awards Committee
Genes, Health, and Disease Study Section, Charter Member
AREDS2 Genetics Advisory Committee
Computational Genomic Epidemiology of Cancer, Steering Committee Member
National Eye Institute, Board of Scientific Counselors
Kidney, Nutrition, Obesity and Diabetes Epidemiology Study Section Panel, Charter Member
Genetic Basis of Disease proposals for King Abdulaziz City for Science and Technology
Path Toward Personalized Medicine, a Thematic Research Program for the Qatar Government
Netherlands Office for Health Research and Development. Grant Reviewer


  1. Lewis, BA, Freebairn, L, Tag, J, Igo, RP Jr, Ciesla, A, Iyengar, SK, Stein, CM, Taylor, HG. Differential Long-Term Outcomes for Individuals With Histories of Preschool Speech Sound Disorders. Am J Speech Lang Pathol 2019; 28 (4): 1582-1596. PubMed PMID:31604025 .
  2. Miller, GJ, Lewis, B, Benchek, P, Freebairn, L, Tag, J, Budge, K, Iyengar, SK, Voss-Hoynes, H, Taylor, HG, Stein, C. Reading Outcomes for Individuals With Histories of Suspected Childhood Apraxia of Speech. Am J Speech Lang Pathol 2019; 28 (4): 1432-1447. PubMed PMID:31419159 .
  3. Halladay, CW, Hadi, T, Anger, MD, Greenberg, PB, Sullivan, JM, Konicki, PE, Peachey, NS, Igo, RP Jr, Iyengar, SK, Wu, WC, Crawford, DC, VA Million Veteran Program. Genetically-guided algorithm development and sample size optimization for age-related macular degeneration cases and controls in electronic health records from the VA Million Veteran Program. AMIA Jt Summits Transl Sci Proc 2019; 2019 : 153-162. PubMed PMID:31258967 PubMed Central PMC6568141.
  4. Joachim, N, Kifley, A, Colijn, JM, Lee, KE, Buitendijk, GHS, Klein, BEK, Myers, C, Meuer, SM, Tan, AG, Flood, V, Schoufour, JD, Franco, OH, Holliday, EG, Attia, J, Liew, G, Iyengar, SK, de Jong, PTVM, Hofman, A, Vingerling, JR, Mitchell, P, Klein, R, Klaver, CCW, Wang, JJ. Joint Contribution of Genetic Susceptibility and Modifiable Factors to the Progression of Age-Related Macular Degeneration over 10 Years: The Three Continent AMD Consortium Report. Ophthalmol Retina 2018; 2 (7): 684-693. PubMed PMID:31047378 .
  5. Retuerto, MA, Szczotka-Flynn, L, Mukherjee, PK, Debanne, S, Iyengar, SK, Richardson, B, Cameron, M, Ghannoum, MA. Diversity of Ocular Surface Bacterial Microbiome Adherent to Worn Contact Lenses and Bacterial Communities Associated With Care Solution Use. Eye Contact Lens 2019; 45 (5): 331-339. PubMed PMID:30724840 .
  6. Lewis, BA, Freebairn, L, Tag, J, Benchek, P, Morris, NJ, Iyengar, SK, Taylor, HG, Stein, CM. Heritability and longitudinal outcomes of spelling skills in individuals with histories of early speech and language disorders. Learn Individ Differ 2018; 65 : 1-11. PubMed PMID:30555216 PubMed Central PMC6294329.
  7. Pollack, S, Igo, RP Jr, Jensen, RA, Christiansen, M, Li, X, Cheng, CY, Ng, MCY, Smith, AV, Rossin, EJ, Segrè, AV, Davoudi, S, Tan, GS, Chen, YI, Kuo, JZ, Dimitrov, LM, Stanwyck, LK, Meng, W, Hosseini, SM, Imamura, M, Nousome, D, Kim, J, Hai, Y, Jia, Y, Ahn, J, Leong, A, Shah, K, Park, KH, Guo, X, Ipp, E, Taylor, KD, Adler, SG, Sedor, JR, Freedman, BI, Family Investigation of Nephropathy and Diabetes-Eye Research Group, DCCT/EDIC Research Group, Lee, IT, Sheu, WH, Kubo, M, Takahashi, A, Hadjadj, S, Marre, M, Tregouet, DA, Mckean-Cowdin, R, Varma, R, McCarthy, MI, Groop, L, Ahlqvist, E, Lyssenko, V, Agardh, E, Morris, A, Doney, ASF, Colhoun, HM, Toppila, I, Sandholm, N, Groop, PH, Maeda, S, Hanis, CL, Penman, A, Chen, CJ, Hancock, H, Mitchell, P, Craig, JE, Chew, EY, Paterson, AD, Grassi, MA, Palmer, C, Bowden, DW, Yaspan, BL, Siscovick, D, Cotch, MF, Wang, JJ, Burdon, KP, Wong, TY, Klein, BEK, Klein, R, Rotter, JI, Iyengar, SK, Price, AL, Sobrin, L. Multiethnic Genome-Wide Association Study of Diabetic Retinopathy Using Liability Threshold Modeling of Duration of Diabetes and Glycemic Control. Diabetes 2019; 68 (2): 441-456. PubMed PMID:30487263 PubMed Central PMC6341299.
  8. Tan, AG, Kifley, A, Holliday, EG, Klein, BEK, Iyengar, SK, Lee, KE, Jun, GR, Cumming, RG, Zhao, W, Wong, TY, Cheng, CY, Mitchell, P, Wang, JJ. Aldose Reductase Polymorphisms, Fasting Blood Glucose, and Age-Related Cortical Cataract. Invest. Ophthalmol. Vis. Sci. 2018; 59 (11): 4755-4762. PubMed PMID:30267098 .
  9. Tedja, MS, Wojciechowski, R, Hysi, PG, Eriksson, N, Furlotte, NA, Verhoeven, VJM, Iglesias, AI, Meester-Smoor, MA, Tompson, SW, Fan, Q, Khawaja, AP, Cheng, CY, Höhn, R, Yamashiro, K, Wenocur, A, Grazal, C, Haller, T, Metspalu, A, Wedenoja, J, Jonas, JB, Wang, YX, Xie, J, Mitchell, P, Foster, PJ, Klein, BEK, Klein, R, Paterson, AD, Hosseini, SM, Shah, RL, Williams, C, Teo, YY, Tham, YC, Gupta, P, Zhao, W, Shi, Y, Saw, WY, Tai, ES, Sim, XL, Huffman, JE, Polašek, O, Hayward, C, Bencic, G, Rudan, I, Wilson, JF, CREAM Consortium, 23andMe Research Team, UK Biobank Eye and Vision Consortium, Joshi, PK, Tsujikawa, A, Matsuda, F, Whisenhunt, KN, Zeller, T, van der Spek, PJ, Haak, R, Meijers-Heijboer, H, van Leeuwen, EM, Iyengar, SK, Lass, JH, Hofman, A, Rivadeneira, F, Uitterlinden, AG, Vingerling, JR, Lehtimäki, T, Raitakari, OT, Biino, G, Concas, MP, Schwantes-An, TH, Igo, RP Jr, Cuellar-Partida, G, Martin, NG, Craig, JE, Gharahkhani, P, Williams, KM, Nag, A, Rahi, JS, Cumberland, PM, Delcourt, C, Bellenguez, C, Ried, JS, Bergen, AA, Meitinger, T, Gieger, C, Wong, TY, Hewitt, AW, Mackey, DA, Simpson, CL, Pfeiffer, N, Pärssinen, O, Baird, PN, Vitart, V, Amin, N, van Duijn, CM, Bailey-Wilson, JE, Young, TL, Saw, SM, Stambolian, D, MacGregor, S, Guggenheim, JA, Tung, JY, Hammond, CJ, Klaver, CCW. Genome-wide association meta-analysis highlights light-induced signaling as a driver for refractive error. Nat. Genet. 2018; 50 (6): 834-848. PubMed PMID:29808027 PubMed Central PMC5980758.
  10. Loomis, SJ, Klein, AP, Lee, KE, Chen, F, Bomotti, S, Truitt, B, Iyengar, SK, Klein, R, Klein, BEK, Duggal, P. Exome Array Analysis of Nuclear Lens Opacity. Ophthalmic Epidemiol 2018; 25 (3): 215-219. PubMed PMID:29182452 PubMed Central PMC5851868.

Publishing impact   

Metrics from Web of Science/publons and Scopus/SciVal: 

  • H-index: 51 
  • Total publications: 175
  • Total citations: 8,885
  • Publications in top-tier journals: 66%
  • Collaborative publishing national/international: 60%/40%

Editorial roles:

  • PLOS Genetics, Guest Editor (current)
  • Kidney International, Editorial Board (past)

Additional Information

Contributions to science:

  • Exploring multi-ethnic genetic predisposition to Age Related Macular Degeneration (AMD) in the Million Veteran Program (MVP) drawing on MVP data as well as data from the International Age Related Macular Degeneration Consortium  
  • Examining the role of genetic and non-genetic factors such as Vitamin D intake, cigarette smoking, lipids, inflammation, oxidative stress and endothelial dysfunction as they inform biomarkers for various diseases. 
  • Developing molecular and statistical methods that stratify risk and phenotypes, straddling both bench and computational science
  • Identification of genes for a variety of ocular and non-ocular diseases

Active grants:

  • NIH/NEI R01: Unraveling the genetic architecture of diabetic retinopathy in South India
  • NIH/ NIDCD R01: Genetic Causes of Severe Developmental Speech Sound Disorder in Families
  • NIH/NIDCD R01: Biological and Behavioral Markers of Persistent Speech Sound Disorders
  • Alcon: Genetic Susceptibility to Contact Lens Microbial Keratitis
  • Veterans Administration:  Million Veteran Program (Project 5 to map genes for ocular diseases)

Student and mentee totals, over Case Western Reserve University career:

  • PhD: 7           
  • Post-doc:  4  
    • A sampling of Case Western Reserve PhD graduates and postdoctoral fellows’ current careers:  
      • Ohio State University, Associate Professor 
      • University of Arkansas, Associate Professor 
      • Silpakorn University, Thailand, Assistant Dean for Academic Affairs and Assistant Professor