[citation needed] MPE research enables identification of a new biomarker for potential clinical utility, using large-scale population-based data (e.g., PIK3CA mutation in colorectal cancer to select patients for aspirin therapy).
[5][6] As an alternative approach, potential risk variants identified by GWAS can be examined in combination with molecular pathology analysis on diseased tissues.
[citation needed] MPE began as analysis of risk factors (e.g., smoking) and molecular pathological findings (e.g., KRAS G12C oncogene mutations in lung carcinoma).
[citation needed] Studies to examine the relationship between an exposure and molecular pathological signatures of disease (particularly, cancer) became increasingly common throughout the 1990s and early 2000s.
[11] The use of molecular pathology in epidemiology lacked standardized methodologies and guidelines as well as interdisciplinary experts and training programs.