Utility Of Fluorescence In Situ Hybridization In The Partial Deletion Of Chromosome 13 In Multiple Myeloma

Objective:Conventional chromosome was used to detect abnormal karytotype from the bone marrow of multiple myeloma patients; analysis of the deletion chromosome13 in MM patients at diagnosis were performed with FISH technique. Clinical significance of FISH-defined partial deletionchromosome13 in MM patients were investigated.Methods:RHG banding was used to study the common cytogenetic changes in bone marrows of 17 preliminary diagnosis MM patients, Other primary laboratory examination and clinical situation of those patients with abnormal karytotype were observed; fluorescence in situ hybridization (FISH ) was performed on bone marrow from 38 patients with MM (including the 17 MM patients who have already been examined by CC)to study the deletion of Rb-1 gene and locus 13q14.3 on chromosome 13. Fisher exact propability was used to study the relations between partial deletion of chromosome13 and clinical features.Results:(1) Conventional chromosome showed that 3 case were failed because the bone marrow prepare grume, 2 cases(NO 2, 5) with complex abnormal karytotype, involving quantity and structural changes of multitude strips chromosome. NO 5 with the del(13q), Both of the two cases with abnormal karytotype were Durie& SalmonⅢstage, the rate of bone marrow plasmablast cell is high(57%, 44%), blood-serumβ2 microglobulin significant high(7.8mg/l, 11.2 mg/l). The control group were prove normal karytotype.(2) 20 out of the 38 cases were found with deletion of chromosome 13; deletion of Rb-1 gene were found in 18 cases; deletion of locus 13q14.3 were found in 16 out of 38 cases; both of the deletions are 14. In those 17 preliminary diagnosis MM patients, 5 cases with del (13q), NO 5 was proved by FISH using probes specific for Rb-1gene,furthermore consisting 1 case whose CC was failure. Fisher exact propability showed that deletion of chromosome 13 was associated with hypso- serum lactic dehydrogenase, hypso- serumβ2 macroglobulin level, low serum-albumin, the high rate of bone marrow plasmablast cell.Conclusion:(1) Complex karyotype are common changes in MM patients and often are detected from those patient with poor situation. (2) Deletion of Rb-1 gene and locus 13q14.3 were both common cytogenetic changes in MM patie- nts with effect on the biological behavior of the disease, and the value of del (13q14) in MM is substantial.(3) FISH could identify complex abnormal karytotype, find or correct the missed or misidentified abnormalities analyses by conventional cytogenetics. FISH was a rapid, accurate and sensitive tech- nique in the analysis of del(13q14) in MM.