Brent L. Williams, Ph.D. is an Assistant Professor of Epidemiology and Pathology & Cell Biology at Columbia University Medical Center in the Center for Infection and Immunity. Dr. Williams has conducted microbiology and epidemiology research for the past 25 years. His research broadly investigates the relationship between the microbiome and human disease, with a focus on the role of the microbiome in the gut-brain and gut-immune axes and its influence on neurodevelopment, behavior, gastrointestinal dysfunction, infection, and cancer. He has led microbiome research efforts for two multi-institutional studies of ME/CFS patients in the U.S.; the Chronic Fatigue Initiative Pathogen Discovery and Pathogenesis Program and the Center for Solutions for ME/CFS. His and his colleagues’ recent research, published earlier this year in Cell Host & Microbe, investigated the gut microbiome of ME/CFS patients compared to healthy individuals in the largest multi-site, case-control study to date. Employing a multi-omics approach, his findings demonstrated substantial gut microbiome dysbiosis in ME/CFS; evidenced by compositional, ecological, and metabolic abnormalities. His findings also demonstrated an intriguing association between gut bacteria and the severity of fatigue symptoms in ME/CFS patients. Dr. Williams’ future research aims to investigate causal relationships between the microbiome and ME/CFS symptoms and to further characterize and validate optimal microbiome-derived biomarkers for ME/CFS.