Many fusion transcripts have already been described in pediatric ALL (e.g., HOOK3-FGFR1, PAX5-DACH1, EP300-ZNF384, PAX5-ETV6, or ZNF618-NUTM1), even though their potential therapeutic or prognostic impact remains to be addressed in more detail [28–33]. Here, HOOK3 is linked to acute lymphoblastic leukemia.