Genetic and transcriptional analysis of spindle checkpoint genes in bone marrow failure patients.
The evolution of bone marrow failure syndromes such as aplastic anemia (AA) to clonal hematologic diseases such as myelodysplastic syndrome is well recognized. Cytogenetic abnormalities are commonly seen late events, particularly aneuploidy of chromosomes 7 and 8. A proportion of bone marrow failure patients may also develop aneuploidy that is detectable by fluorescence in situ hybridization but not by standard cytogenetic analysis. The molecular basis for aneuploidy in this setting is currently unknown but may include abnormalities in the mitotic spindle checkpoint. For this reason, we searched for mutations in the mitotic spindle checkpoint genes hBUB1 and hMAD2, and also examined the expression of hBUB1 in cells of bone marrow failure patients. No pathogenic mutations were found in 59 patients. Of 170 bone marrow failure patients, less than one-third expressed hBUB1 transcript. Gene expression profiling confirmed a significant down-regulation of hBUB1 message in patients. We conclude that mutations in mitotic spindle checkpoint genes do not account for aneuploidy in marrow failure states. However, we cannot exclude epigenetic inactivation of hBUB1 as a potential mechanism in some patients.
Yamaguchi
Hiroki
H
Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Aridgides
Laura J
LJ
Zeng
Weihua
W
Osgood
Christopher
C
Young
Neal S
NS
Liu
Johnson M
JM
D000782:Aneuploidy; D001855:Bone Marrow Diseases / Q000235:genetics*; D002135:Calcium-Binding Proteins / Q000235:genetics; D018797:Cell Cycle Proteins; D020732:Cytogenetic Analysis; D004252:DNA Mutational Analysis; D015536:Down-Regulation; D018816:Genes, cdc; D006801:Humans; D064246:Mad2 Proteins; D011494:Protein Kinases / Q000032:analysis / Q000235:genetics; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger / Q000032:analysis; D012097:Repressor Proteins; D008941:Spindle Apparatus; D014158:Transcription, Genetic
D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; C577697:MAD2L1 protein, human; D064246:Mad2 Proteins; D012333:RNA, Messenger; D012097:Repressor Proteins; D011494:Protein Kinases; C584277:BUB1 protein, human; C090464:Bub1 spindle checkpoint protein; D017346:Protein Serine-Threonine Kinases