 Jonasson completed her residency at the University of Illinois.After her residency, Jonasson spent a year at Walter Reed Army Institute of Research in Washington D.C. where she had a postdoctoral Fellowship under Dr. Elmer Becker in which she studied immunohistochemistry.She then had another year long research and clinical fellowship under at Massachusetts General Hospital in Boston where she studied transplantation immunobiology under Dr. Henry J. Winn and Dr. Paul S. Russell.