There was a significant negative correlation (r ≤ −0.3) between PLOD1 expression and DNA methylation in UVM, LIHC, RAAD, UCS, SARC, mesothelioma (MESO) and pheochromocytoma and paraganglioma (PCPG). The gene discussed is PLOD1; the disease is hereditary pheochromocytoma-paraganglioma.