3)The Way We Use the Molecular Methods for Clinics in Hematological Disorders.

The use of molecular methods have identified genes and genetic changes associated with specific hematological disorders. The best known hematologic melecular markers include inherited erythrocyte and homeostasis disorders. Recently we detected a Japanese family with an autosomal dominant inheritance primary familial and congenital polycythemia （PFCP）. Sequence analysis of RT－PCR product amplified from C－terminal regibn of erythropoietin receptor （EpoR） transcripts in these affected family member’s revealed that they were all heterozygous for C and T bases at position 5986, which implied the genetic mutation （C to T） on one allele of EpoR. Molecular changes associated with specific leukemias and lymphomas’ are useful in diagnosis, staging, prognosis, monitoring of residual disease, and evaluation of therapies. The vast majority of these changes are chromosomal translocation and identification of genes involved in the translocation revealed the abnormal chimeric genes. The high sensitivity of PCR amplification enabled us to detect minimal residual diseases and to detect early relapse. The rearrangements within genes of the immune system are good lineage markers and also good markers for clonal expansion in the tissues. STR （short tandem repeat） loci consist of short, repetitive sequence elements of 3 to 7 base pairs in length. These abundant repeats are well distributed throughout the human genome and are a rich source of highly polymorphic markers which often may be detected using the PCR. We have used these polymorphic markers to determine the engraftment of bone marrow donor hematopoietic stem cells or to detect the relapse of recipient’s leukemic cells as soon as possible