A CASE OF MYELODYSPLASTIC SYNDROME WITH AN INTRONIC POINT MUTATION OFTHE P53 TUMOR-SUPPRESSOR GENE AT THE SPLICE DONOR SITE

We analysed genomic DNA and mRNA of the p53 gene in a case of myelodys plastic syndrome (MDS) with monosomy of chromosome 17, DNA analysis re vealed a mutation at the splice donor site (GT to GC) of intron 5. mRN A analysis revealed the presence of abnormal splicing with 46 nucleoti de deletion in exon 5, producing a downstream frame shift and a predic ted truncated protein which lacked normal function. The p53 gene mutat ion at the splice donor site contributes to the inactivation of the p5 3 gene function and may play an important role in the pathogenesis, pr ogression and therapeutic responsiveness of MDS.