The cells comprising the LAM lesions and angiomyolipomata appear to arise from a common source.[3, 4] Approximately, 80% of patients with TSC develop renal angiomyolipomata and mostly because of a definitive mutation of the TSC1 or TSC2 gene.[4] Renal angiomyolipomata may occur unilaterally or bilaterally and historically were the most common cause of premature mortality in adults with TSC.[5] Angiomyolipomata are mostly asymptomatic and slow growing. The gene discussed is TSC1; the disease is tuberous sclerosis.