A second aspect that is often underestimated is shown by biopsies of invasive cervical carcinoma (squamous cell carcinomas and adenocarcinomas) with genotyped HPV, in which results confirmed the presence of a large quantity of expressed retroelements (L1) correlated with DNA methyltransferase 1 expression [69,72,73]. This evidence concerns the gene DNMT1 and squamous cell carcinoma.