High-dose interleukin-2 (HD IL-2) has been reported to obtain an objective clinical disease regression in 15-17% of patients with metastatic melanoma (MM) and renal cell carcinoma (RCC), with 6-8% of cases experiencing a durable complete response in all metastases (1–3). The gene discussed is IL2; the disease is hereditary clear cell renal cell carcinoma.