An interesting study by Jung et al. [24] on a group of patients with differentiated thyroid cancer who underwent total thyroidectomy and radioactive iodine (RAI) treatment showed that total cholesterol, triglycerides, low-density lipoprotein cholesterol, apoB, and the apoA-I/II ratio were significantly elevated in RAI-treated patients and returned to baseline values after levothyroxine replacement. The gene discussed is APOB; the disease is thyroid cancer.