The biomarkers for lymphoma development include parotid or submandibular swelling, cryoglobulinemia, rheumatoid factor, and low C4 levels, among others, which have been validated in previous studies [48], [49], [50] highlighting the significance of parotid or submandibular gland swelling, low C4, rheumatoid factor and cryoglobulinemia for lymphoma development. The gene discussed is C4A; the disease is lymphoma.