One patient with a pathogenic germline variant in APC also had biallelic (compound heterozygous) pathogenic MUTYH variants, and three patients (3%) had monoallelic variants in MUTYH (one patient also had PGV in MLH1) which is reported in 1–2% of the general population [22], and in 3% in a Spanish multicenter early onset CRC (<50 years old) population [8]. The gene discussed is MLH1; the disease is colorectal carcinoma.