Available past studies reached contradictory conclusions about its pathogenicity reporting harmful in silico predictions [4], absence of splicing or mRNA alteration [5], presence in patients with a defective MMR tumor [6], co-occurrence with clearly pathogenic MMR mutations [7], apparent segregation with disease [8], and a majority of non-altered in vitro functional studies [9], [10]. This evidence concerns the gene MRC1 and neoplasm.