P53 mutation in advanced stage of primary myelodysplastic syndrome.

Polymerase chain reaction and single strand conformation polymorphism (PCR-SSCP) analysis of the p53 tumor suppressor gene (from exon 2 to 9) was performed on samples from 47 adult patients with primary myelodysplastic syndrome (MDS). Point mutation was found in 5 (11%) patients: exon 7 in 3, exon 4 in 1 and intron 5 in 1. The frequency of p53 mutation was significantly higher at advanced stages (p = 0.048) and higher in patients with abnormal karyotypes (p = 0.023). Although all of the p53 mutations were detected at advanced stages, four of them were detected at initial diagnosis with very short survival. Sequential SSCP analysis in 20 transformed MDS patients revealed only one new p53 mutation during progression from early MDS phases. The results suggest that p53 mutation might occur as an early genetic event and is probably associated with rapid progression and poor survival in some MDS patients.