NOTCH1 and B-cell chronic lymphocytic leukemia: Similarly, we also observe co-mutations characteristic of chronic lymphocytic leukemia (CLL); 6 out of 16 (37.5%) cases of trisomy 12 co-occurred with a mutation in NOTCH1, MYD88, or FBXW7; 2 out of 9 (22%) deletions on chr13q co-occurred with a ATM mutation34.