Interphase FISH for Y Chromosome, VNTR Polymorphisms, and RT-PCR for BCR-ABL in the Monitoring of HLA-Matched and Mismatched Transplants

Thirty-six sex-mismatched transplants were studied using fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) methods. Molecular cytogenetics was performed using interphase FISH with a centromeric probe for chromosome Y, and PCR amplification was performed with a set of VNTR microsatellite loci. In addition, reverse transcriptase-PCR (RT-PCR) for BCR-ABL fusion was used to investigate cases of Philadelphia chromosome (Ph)-positive chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL). Our integrated approach of post-transplant monitoring was helpful in documenting successful transplants and in controlling the size of Ph-positive clones in CML. A striking overlap was found between results from FISH analysis and PCR for polymorphic loci.