JAK2(V617F) mutation in myelodysplastic syndrome (MDS) with del(5q) arises in genetically discordant clones.

The 2008 World Health Organization (WHO) proposed revision of the classification of MDS recognizes a deletion (5q) subtype with mutation of Janus kinase-2 (JAK2(V617F)). We investigated the clonal origin of this gene mutation in a patient with del(5q) MDS presenting with thrombocytosis and normal hemoglobin. Analysis of colony forming units-granulocyte-monocyte (CFU-GM) and erythropoietin-independent growth of bone marrow (BM) and peripheral blood (PB) burst forming units-erythroid (BFU-E) showed that del(5q) and JAK2(V617F) existed in progenitors derived from independent clones.

Frequency, hematopathology, and detection of a new isodicentric variant of deletion 20q.

The ider(20)(p11.21)del(20)(q11q13) anomaly was recognized only recently. Thus, its frequency and clinical significance has not been extensively studied.

Efficacy of conventional cytogenetics and FISH for EGR1 to detect deletion 5q in hematological disorders and to assess response to treatment with Lenalidomide.

In clinical practice, whether FISH for EGR1 in interphase nuclei has similar efficacy to detect deletion 5q anomalies as conventional cytogenetic studies is unknown. We compared conventional cytogenetics and FISH for 145 patients with deletion 5q and detected this anomaly by both methods in 144. Nine patients with myelodysplasia were studied before and after treatment with Lenalidomide and results were concordant for 28 of 29 specimens.

Prospective evaluation of clonal evolution during long-term follow-up of patients with untreated early-stage chronic lymphocytic leukemia.

Purpose: Retrospective studies suggest cytogenetic abnormalities detected by interphase fluorescent in situ hybridization (FISH) can identify patients with chronic lymphocytic leukemia (CLL) who will experience a more aggressive disease course. Other studies suggest that patients may acquire chromosome abnormalities during the course of their disease. There are minimal prospective data on the clinical utility of the widely used hierarchical FISH prognostic categories in patients with newly diagnosed early-stage CLL or the frequency of clonal evolution as determined by interphase FISH.

Loss of TP53 is due to rearrangements involving chromosome region 17p10 approximately p12 in chronic lymphocytic leukemia.

Loss of tumor protein 53 (TP53) has been associated with aggressive disease and poor response to therapy in B-cell chronic lymphocytic leukemia (B-CLL). TP53 is located at chromosome band 17p13 and its absence can be detected by fluorescence in situ hybridization (FISH) in the interphase nuclei of 8-10% patients with B-CLL. To study the cytogenetic mechanism for loss of TP53, metaphase and interphase FISH studies were conducted on 16 B-CLL patients to investigate 17p10 to 17p12, a chromosome region known to be rich in low-copy DNA repeats.