The two most common MUTYH gene PVs in Western Europeans and North Americans are c.1187G>A (p.Gly396Asp), also known as G396D and G382D, and c.536A>G (p.Tyr179cys), also referred to as Y179C and Y165C; the effect of such mutations, when present in homozygosity or double heterozygosity, is impaired MUTYH activity leading to MAP syndrome with different types of polyposis and cancer [2]. The gene discussed is MUTYH; the disease is familial adenomatous polyposis 2.