Cytogenetic profile of acute lymphocytic leukemia patients: report of a novel translocation t(4;13) (q21 x 3; q35) from an Indian population.

Acute lymphocytic leukemia (ALL) is a malignant neoplasm characterized by clonal proliferation, decreased apoptosis and accumulation of immature lymphoid cells in the bone marrow as well as the peripheral blood. The aim of this study was to determine the overall cytogenetic profile of Indian ALL patients along with their frequency and distribution pattern. A total of 75 ALL subjects were included in the study. The major outcome of the work was identification of a novel translocation t(4;13) (q21 x 3;q35) that has not yet been reported. In addition, a few rare chromosomal aberrations such as t(4;16) (p16;q12 x 2) and t(7;10)(q36;q21 x 2) were also detected. Overall, of 75 cases, 67 (89 x 33%) were successfully karyotyped. Normal and abnormal karyotypes were seen in 38 (56 x 7%) and 29 (43 x 3%) cases respectively. Various other abnormalities were hyperdiploidy (20 x 68%), hypodiploidy (10 x 34%), t(8;14) (3 x 44%), t(9;22) (6 x 9%), t(4;16) (3 x 44%), t(7;10) (3 x 44%) and gain of chromosome 8, 13, 16, and 22 was seen in one case each (3 x 44%). Deletions in chromosome 5, 9 and 11 were found to be 3 x 44, 6 x 89 and 6 x 89% respectively, while complex and other aberrations were detected in 3 x 44 and 13 x 8% cases. Finally, we conclude that cytogenetic analysis has an important role in routine genetic diagnostic workup and management of ALL patients.