RAG1 and precursor B-cell acute lymphoblastic leukemia: Therefore, we selected a panel of genes including IKZF1, CDKN2A/B, PAX5, BTG1, TBLXR1, RAG1, RAG2 and ETV6 that were described as being involved in the pathogenesis of B-ALL previously, we expanded the panel by adding genes that were found to have minor aberrations in patients of this cohort, and we analyzed gene copy number alterations in patients.