In this study, we screened for germline mutations in 36 genes across five categories of CRC cases, including (1) Familial Colorectal Cancer Type X (FCCTX) which meet the Amsterdam Criteria I for Lynch Syndrome, but have normal mismatch repair function (microsatellite stable [MSS] and/or normal expression of four MMR proteins encoded by MLH1, MSH2, MSH6, and PMS2 by IHC) in the tumor (Lindor et al. Here, MLH1 is linked to colorectal carcinoma.