Andrew received his Ph.D. in Microbiology from the University of Texas Health Science Center at San Antonio in 1992, and a postdoctoral fellow in Molecular Biology at Princeton University from 1992-1996. He began his career at the University of Nebraska-Lincoln as an Assistant Professor in 1996 and is currently a Professor in the Department of Food Science and Technology. His research program has emphasized applications of population genomics and quantitative genomics to food safety and study of the human gut microbiome. In 2016, he helped establish the Nebraska Food for Health Center.