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Background & objectives: Chronic myelogenous leukaemia (CML) is the commonest leukaemia in Asia. There is a paucity data on cytogenetic and molecular analyses of Indian CML patients. This apparently reflects the low availability of cytogenetic and molecular techniques in our country. This study aimed to document various types of BCR-ABL fusion transcripts in different phases of CML and to compare the Ph chromosome positivity/negativity vis-a-vis BCR-ABL fusion transcripts in adult CML patients. Methods: Between June 2004 and February 2009, 208 patients were diagnosed as CML in chronic phase (CP), accelerated phase (AP) and blast crisis (BC), according to standard criteria. Cytogenetic and molecular genetic analyses were performed in all patients. Various types of BCR-ABL hybrid transcripts were compared with phases of CML and cytogenetic abnormalities. Results: Among 208 CML patients, b3a2 BCR-ABL transcripts were most commonly detected (66.82%) followed by b2a2 (28.84%), b3a2 + b2a2 (3.36%), b3a2 + e19a2 (0.48%) and b2a2 + e19a2 (0.48%). b3a2 transcripts were more frequently detected than b2a2 transcripts, in the whole group of 208 as well as in 183 CML-CP patients (P<0.0001). Ph chromosome was positive in 135 of 139 patients with b3a2 transcripts and 56 of 60 patients with b2a2 transcripts, difference not being significant. Additional cytogenetic abnormalities detected in 3.8 per cent patients in CML-CP and 44 per cent patients in CMLAP/ BC, did not show predilection for any BCR-ABL transcript type. Interpretation & conclusions: This study documents higher Ph positivity (96.15%) by cytogenetic analysis among CML patients, as confirmed by qualitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis in a large patient group from north India. Both the techniques contribute towards understanding the disease biology, and have important implications for diagnosis and management of CML patients. [ABSTRACT FROM AUTHOR]

Most cases of leukemia show hTERT and WT1 gene overexpression. However, the role of these genes in the progression and monitoring of chronic myeloid leukemia (CML) has not been very well explored. Two hundred and eight patients diagnosed as having CML in chronic phase (CP), accelerated phase (AP), and blast crisis (BC) were studied. Real-time polymerase chain reaction (PCR) was performed for comparative quantification of BCR--ABL, hTERT, and WT1 gene expression. The expression levels of the three genes were compared among the three phases and seven imatinib-naive and -treated subgroups. Among the three major groups, the gene expression levels of hTERT ( p < 0.01) and WT1 ( p < 0.01) were significantly different. Freshly diagnosed, imatinib-responsive, and -unresponsive patients among these revealed interesting changes in hTERT and WT1 gene expression profiles, especially in 25 patients with CML in whom sequential samples were analyzed. Our results showed that hTERT and WT1 gene expression analyses provided relevant information for the understanding of disease progression and indicate their possible usefulness as surrogate markers for treatment monitoring. [ABSTRACT FROM AUTHOR]