Moreover, several studies have demonstrated that PAX1 methylation increases following increased disease grade: PAX1 methylation in SCC > high − grade squamous intraepithelial lesion (HSIL) > low − grade squamous intraepithelial lesion (LSIL) > normal tissue [38, 39]. The gene discussed is PAX1; the disease is squamous cell intraepithelial neoplasia.