GENETIC INSTABILITY OF MICROSATELLITES IN HEMATOLOGICAL NEOPLASMS

Genetic instability has been recently related to point mutations on ge nes involved in DNA repair pathway of errors produced during replicati on, These molecular alterations have been described in hereditary and sporadic colon carcinomas and related tumors. To examine genetic insta bility on lympho- and myeloproliferative processes, we analyzed the be haviour of 10 microsatellite markers and one VNTR on different chormos omes in 10 patients with non-Hodgkin lymphomas (NHL), one patient with acute lymphoblastic leukemia (ALL) and 10 patients with acute myeloid leukemia (AML). Mobility shifts were found in three of those cases. O ne of them showed genetic instability for several markers - microsatel lites and VNTR - and the other two showed differences for only one mar ker. As a correlation between point mutations in MSH2 gene and the pre sence of genetic instability in hereditary non-polyposis colon cancer (HNPCC) and related tumors has been found, we analyzed the sequence of a conversed region of this gene in the cases showing this phenomenon, We only found a polymorphism, previously described, in 669 codon from cDNA.