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Texas Medical Center

Phone: 832-824-3710
Fax: 832-825-1165


1102 Bates Avenue
Feigin Tower, Suite 830
Houston, TX 77030

James Versalovic, MD, PhD

Pathologist-In-Chief and Chair of Texas Children’s Department of Pathology

Milton J. Finegold Professor and Vice Chair, Pathology & Immunology, Baylor College of Medicine


School Education Degree Year
Massachusetts General Hospital Fellowship Pathology 1999
Massachusetts General Hospital Residency Pathology 1998
Baylor College of Medicine Medical School Doctor of Medicine 1995
Baylor College of Medicine Postgraduate Education Doctor of Philosophy 1994


Dr. Versalovic serves as Pathologist-In-Chief at Texas Children’s Hospital and Director of Texas Children’s Microbiome Center. He is the Milton J. Finegold Professor and Vice Chair of Pathology & Immunology at Baylor College of Medicine.  He also is Professor of Molecular and Human Genetics, Molecular Virology & Microbiology, and Pediatrics, and Co-Director of the Medical Scientist (MD/PhD) Training Program at Baylor College of Medicine.

Dr. James Versalovic received his M.D. with Honors at Baylor College of Medicine (BCM) in 1995 and his Ph.D. in Cellular and Molecular Biology at BCM in 1994. He pursued clinical pathology/medical microbiology residency training at the Massachusetts General Hospital and Harvard Medical School. He also completed a postdoctoral research fellowship in the Division of Comparative Medicine at the Massachusetts Institute of Technology (MIT). Dr. Versalovic joined the medical staff as a clinical pathologist at the Massachusetts General Hospital and served as Assistant Professor of Pathology at Harvard Medical School. He is board-certified in clinical pathology, molecular genetic pathology, and molecular diagnostics.

Dr. Versalovic directs the delivery of diagnostic services and laboratory medicine at Texas Children’s by serving as Director of Laboratories, for the medical center campus. Dr. Versalovic’s main clinical interests are medical microbiology, molecular diagnostics of infectious diseases, microbiome science applies to pediatric gastroenterology, genomic and metagenomic medicine, and molecular pathology. Dr. Versalovic has created the first microbiome center based in a children’s hospital and the first therapeutic microbiology fellowship program in the country. He has helped create the new field of metagenomic medicine by exploring ways that metagenomics and microbial manipulation can be used to diagnose and treat human diseases. He served as Editor-in-Chief of the Manual of Clinical Microbiology, the “bible” of laboratory-based diagnosis of human infections.

As Principal Investigator since 1999, Dr. Versalovic’s primary research areas include gastrointestinal microbiology, the human gastrointestinal microbiome and mechanisms of signaling between the microbiome and human cells. With a focus on the gastrointestinal microbiome, beneficial microbes and chronic disease, Dr. Versalovic’s research team has studied mouse models and human subjects/patients to understand basic concepts of microbiome science, human microbiology, and how the microbiome impacts human development and children’s health. Dr. Versalovic is advancing metagenomic medicine and its applications in chronic gastrointestinal disorders such as pediatric irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). His research program has been supported by the U.S. National Institutes of Health, Department of Defense, and Crohn’s and Colitis Foundation of America. Dr. Versalovic has authored more than 135 primary manuscripts, more than 30 book chapters, and 2 patents.

News Articles:

Microbiome science may help doctors to improve treatment for children with IBS 


Organization Name Role
American Gastroenterological Association Fellow
American Society for Clinical Pathology Fellow
American Society for Microbiology Member
Association for Molecular Pathology Member
College of American Pathologists Fellow

Selected Publications

Spinler JK, Sontakke A, Hollister E, Venable S, Oh P, Balderas M, Saulnier D, Mistretta TA, Devaraj S, Walter J, Versalovic J, Highlander S. From prediction to function using evolutionary genomics: Human-specific ecotypes of Lactobacillus reuterihave diverse probiotic functions. Genome Biology andEvolution 2014 July; 6(7): 1772-1789 doi:10.1093/gbe/evu137.

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Awards & Honors

Dr. Versalovic has received several notable awards including the Lansky Award as a national leader in pathology under the age of 45 from the College of American Pathologists Foundation. He also received the BioGaia Ivan Casas Probiotics Research Award (2007) and the BCM Graduate School of Biomedical Sciences Distinguished Alumnus Award (2010).

* Texas Children's Hospital physicians' licenses and credentials are reviewed prior to practicing at any of our facilities. Sections titled From the Doctor, Professional Organizations and Publications were provided by the physician's office and were not verified by Texas Children's Hospital.