An apparent interlocus gene conversion-like event at a putative tumor suppressor gene locus on human chromosome 6q27 in a Burkitt's lymphoma cell line.
A region of minimal deletion in B-cell non-Hodgkin's lymphoma (B-NHL) has recently been defined between D6S186 and D6S227 spanning 5-9 Mb at 6q26-q27, predicting the presence of at least one tumor suppressor gene (TSG) at this locus. During the construction of a deletion map in the B-NHL tumor panel, we report the identification of a Burkitt's lymphoma cell line, BL74, having an apparent homozygous deletion at the D6S347 locus, internal to the critical region. Since this case may facilitate the localization of the target TSG, a detailed structural molecular characterization and search for candidate genes were undertaken at this locus. While BL74 underwent a loss of heterozygosity at 6q26-q27, D6S347 was also likely subjected to a somatic interlocus gene conversion-like event between two homologous but distinct loci, resulting in the homozygous replacement of a 1860- to 2067-bp segment of one locus with the corresponding segment copied from the other locus. Two genes at this locus were identified, but their lack of expression in B-cell lineages tentatively excludes them as candidate TSGs. Another still unidentified gene at this locus may be disrupted by the gene conversion-like event, which would represent a novel mechanism of TSG inactivation.
Hauptschein
R S
RS
Institute of Cancer Genetics, Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
Gaidano
G
G
Rao
P H
PH
Scotto
L
L
Edwards
Y H
YH
Chaganti
R S
RS
Dalla-Favera
R
R
D000483:Alleles; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002051:Burkitt Lymphoma / Q000235:genetics*; D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D005091:Exons; D005785:Gene Conversion; D017353:Gene Deletion; D016147:Genes, Tumor Suppressor / Q000235:genetics*; D006801:Humans; D019656:Loss of Heterozygosity; D008957:Models, Genetic; D008969:Molecular Sequence Data; D012150:Polymorphism, Restriction Fragment Length; D012313:RNA / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D012313:RNA