Frequency and clinical impact of ETV6/RUNX1, AF4‑MLL, and BCR/ABL fusion genes on features of acute lymphoblastic leukemia at presentation
Background: Variations in disease presentation and outcome of leukemia treatment has been associated with the presence of certain mutant genes. Three major translocations (ETV6‑RUNX1, BCR‑ABL, and AF4‑MLL) in acute lymphoblastic leukemia (ALL) have been shown to affect treatment outcome. This study is aimed at assessing the relationship between these translocations and the presence of other indicators of disease severity (white cell count, hemoglobin concentration, platelet count, and hematocrit) in ALL.
Patients and Methods: Forty chemotherapy naïve patients aged between 9 months and 54 years had their marrow samples analyzed for the prevalent mutations. Their clinical and laboratory details on presentation were also obtained.
Results: Abnormal genes detected were BCR/ABL1 major transcript in 5 (12.5%), ETV6/RUNX1 in 2 (5.0%), MLL/AF4 none and none of the patients had more than one fusion gene. There was no relationship between the presence of these fusion genes and the clinical and laboratory features of ALL. An association exists between the fusion genes and ethnic origin of the patients (P = 0.005). There is no significant association between the abnormal fusion genes detected and some laboratory features of prognostic importance, which include total white blood cell count (P = 0.416) and FAB subtype (P = 0.576).
Conclusion: Presence of fusion the genes BCR/ABL1, ETV6/RUNX1, and MLL/AF4 does not have any impact on the clinical and laboratory features of ALL at presentation.
Key words: Acute lymphoblastic leukemia, BCR/ABL1, ETV6/RUNX1, fusion genes, MLL/AF4