The vast majority of patients with uterine LMS carry at least one mutation in either tumor protein 53 (TP53), retinoblastoma (RB1), phosphatase and tensin homolog deleted on chromosome 10 (PTEN), or alpha-thalassemia/mental retardation, X-linked (ATRX) [49]. The gene discussed is ATRX; the disease is thalassemia.