Variant-Class 5 includes coding sequence variation resulting in a stop codon (nonsense or frameshift), splicing aberration variants by mRNA assay, large genomic deletions or duplications, abrogated mRNA/protein function variants based either on laboratory assays, on evidence for cosegregation with disease, and on MSI tumor, and/or loss of MMR protein expression. Here, MRC1 is linked to neoplasm.