John M. Greally, MD

Director, Center for Epigenomics; Attending physician
Professor and Chief Division of Genomics Department of Genetics

Contact Information

P: 718.741.2323 F: 718.920.6506

Primary Location

The Children's Hospital at Montefiore3415 Bainbridge AvenueBronx, NY 10467-2403


  • Specialties & Focus


    • Clinical Genetics
  • Education & Training


    Residency Program

    Childrens Hospital of Pittsburgh / UPMC Health Sys


    Yale University

  • Biography

    Personal Biography

    John M. Greally, DMed, PhD, MB, BCh, BAO, is Chief of the Division of Genomics in the Department of Genetics, Director of the Center for Epigenomics and Professor of Genetics and Pediatrics at Montefiore Einstein. Dr. Greally is a specialist in clinical genetics, with an emphasis on rare diseases and congenital conditions. He has expertise in medical genomics, the use of advanced genomic technologies to diagnose genetic conditions.

    Dr. Greally obtained his Bachelor’s degree in Medicine, Surgery and Obstetrics in 1988 from the National University of Ireland in Galway, Ireland. He received his Doctorate of Philosophy in 1999 and his Doctorate of Medicine in 2016 from the same institution.

    Building on his clinical focus, Dr. Greally runs a research program that uses genomic technologies, advanced data analysis techniques and stem cell systems to understand the mechanisms of human genetic diseases, with a focus on rare DNA sequence variants in the non-coding majority of the human genome. He is focused on improving our ability to diagnose rare diseases and on the equitable provision of genomics services to populations of all ancestries. As a clinician working in the most diverse county in the US, Dr. Greally is committed to delivering medical genomics care to minority communities and learning how to perform research studies with and directed by these vulnerable and exploited groups. He has also initiated a startup business, Latent Genomics, to allow the effective use of medical genomics in clinical care.

    Dr. Greally holds a United States Patent titled Methods for determining cytosine methylation in DNA and uses thereof. His work has been published in numerous peer-reviewed journals, chapters and books, and he has presented nationally and internationally. He sits on the editorial board of Epigenetics and Chromatin (BioMed Central) and is a section editor for Epigenetics at PLOS Genetics.

    Dr. Greally is board certified in pediatrics by the American Board of Pediatrics and in clinical genetics and genomics by the American Board of Medical Genetics. He is a member of the American Society of Human Genetics and a fellow of the American College of Medical Genetics and Genomics. Dr. Greally has been appointed president of the New York Celtic Medical Society from 2021 to 2023, and in 2014 he won Mentor of the Year in Basic Science from Montefiore Einstein.

  • Locations

    Primary Location

    The Children's Hospital at Montefiore

    3415 Bainbridge AvenueBronx, NY 10467-2403

    P: 718.741.2323 F: 718.920.6506

    Additional Locations

    CERC/Rose F. Kennedy Center
    1225 Morris Park AvenueBronx, NY 10461 Additional Details
    Montefiore at 1250 Waters Place
    1250 Waters PlaceBronx, NY 10461-2720 P: 718.741.2450 Additional Details