Investigation of TEL/AML1 and BCR/ABL genes fusion in Acute lymphoblastic leukemia (ALL) Patients and Follow-up Study in 25 Bone Marrow Transplanted (BMT) Patients Using Interphase Fluorescence In Situ Hybridization (FISH).

BCR/ABL fusions in hematopoeitic cells are known to induce resistance to apoptosis and cell changes in response to cell-cell and cell-matrix interactions, on the other hand, patients with TEL/AML1 gene fusions respond differently to treatment, depending on therapeutic protocols. We conducted a prospective cohort study to investigate how these translocations affect a person’s quality of life, and to evaluate their responses to bone marrow transplantation therapy.Methods and Materials: TEL, AML1, ABL and BCR probes were applied to cells during interphase, using cytogenetic techniques and FISH analysis to obtain the karyotype of 100 patients, which included genes involved in fusion, signal distributions, age, sex, positive familial background, and responses to therapies. After BMT was performed in 25 patients, all of the above data was collected once again and the results were compared. In our study, 46% of child patients demonstrated an abnormal FISH pattern (23% with fused ABL/AML1, 3% with deletion, 7% with a gain in TEL gene, and 3% and 10% with deletion and a gain in AML1 genes, respectively. In adults, 27% had an abnormal FISH pattern, while 3% had fused TEL/AML1 genes and other abnormalities, as was evident in children. A gain in gene copy occured twice as often as a loss in gene copy, except for child ALL patients with t(12;21), where in 58% of cases, lost TEL gene children with t(12;21) had longer survival periods, while adults with t(9;22) had shorter ones. Post BMT revealed that 65% of BM cells karyotyped normal, compared to 24% pre-BMT. WBC count increased positively with the onset of ALL, although an increase in WBC count decreased survival time. A relationship between positive familial background and ALL was also seen. FISH is the better method for diagnosing genetic disorders in ALL patients compared to other methods.