Out of the 11 patients, 9 (0.7%) were finally diagnosed as having Lynch syndrome; the responsible genes included MLH1 (n = 1), MSH2 (n = 4), EPCAM (n = 1) and MSH6 (n = 3).
Genetic counseling and germline analysis for mutations in genes associated with Lynch syndrome (MLH1, MSH2, MSH6, PMS2, and EPCAM) were offered to individuals with PREMM<sub>1,2,6</sub> scores of 5% or higher.
Among confirmed LS, path_MLH1 variants were most commonly identified in Peru (82%), Mexico (80%), Chile (60%), and path_MSH2/EPCAM variants were most frequently identified in Colombia (80%) and Argentina (47%).
Moreover, the mutations in the EpCAM gene lead to congenital tufting enteropathy, severe intestinal epithelium homeostasis disorders, and Lynch and Lynch syndrome.
We found a novel large EPCAM-MSH2 duplication associated with LS and the presence of LOHs in regions containing numerous tumor suppressors, raising the hypothesis that these alterations could contribute to cancer susceptibility.