Reports indicate that antioxidants such as SOD, GSH-Px, catalase (CAT), and vitamins C and E are lower in patients with multiple myeloma, while serum levels of oxidative stress markers such as malondialdehyde (MDA) and advanced oxidation protein products (AOPP) are higher compared to healthy individuals [20,21,22,23]. The gene discussed is CAT; the disease is AL amyloidosis.