The utility of spectral karyotyping in the cytogenetic analysis of newly diagnosed pediatric acute lymphoblastic leukemia.
We applied multicolor spectral karyotyping (SKY) to a panel of 29 newly diagnosed pediatric pre B-cell ALLs with normal and abnormal G-banded karyotypes to identify cryptic translocations and define complex chromosomal rearrangements. By this method, it was possible to define all add chromosomes in six cases, a cryptic t(12;21)(p13;q11) translocation in six cases, marker chromosomes in two cases and refine the misidentified aberrations by G-banding in two cases. In addition, we identified five novel non-recurrent translocations - t(2;9)(p11.2;p13), t(2;22) (p11.2;q11.2), t(6;8)(p12;p11), t(12;14)(p13;q32) and t(X;8)(p22.3;q?). Of these translocations, t(2;9), t(2;22) and t(12;14) were identified by G-banding analysis and confirmed by SKY. We characterized a t(12;14)( p13;q32) translocation by FISH, and identified a fusion of TEL with IGH for the first time in ALL. We identified a rearrangement of PAX5 locus in a case with t(2;9)(p11.2;p13) by FISH and defined the breakpoint telomeric to PAX5 in der(9)t(3;9)(?;p13). These studies demonstrate the utility of using SKY in combination with G-banding and FISH to augment the precision with which chromosomal aberrations may be identified in tumor cells.
Lu
X Y
XY
Division of Hematology-Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
Harris
C P
CP
Cooley
L
L
Margolin
J
J
Steuber
P C
PC
Sheldon
M
M
Rao
P H
PH
Lau
C C
CC
D000208:Acute Disease; D000293:Adolescent; D019677:Artificial Gene Fusion; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002871:Chromosome Banding; D002877:Chromosomes, Human / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D051757:PAX5 Transcription Factor; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000235:genetics*; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins / Q000235:genetics; D032681:Spectral Karyotyping; D014157:Transcription Factors / Q000235:genetics; D014178:Translocation, Genetic; D000097764:ETS Translocation Variant 6 Protein
D004268:DNA-Binding Proteins; D051757:PAX5 Transcription Factor; D050783:Proto-Oncogene Proteins c-ets; D012097:Repressor Proteins; D014157:Transcription Factors; D000097764:ETS Translocation Variant 6 Protein; C497281:PAX5 protein, human