Ms. Johnson earned her BS degree in General Science from the University of Iowa in 1981 and followed with her Medical Technology certification in 1982, also from the University of Iowa. She worked in the hematology laboratory at the University of Iowa Hospital, in the hematology department of Smith-Kline Beecham, and at a reference laboratory specializing in the diagnosis of auto-immune disorders.

She joined Valdes Laboratories in 1995 working in the Diagnostic Reference Laboratory and participated in numerous clinical trials of new assays and instrumentation. She joined PGXL Laboratories in 2001.

Ms. Johnson has been a registered member of the American Society for Clinical Pathologists since 1982.