The Possible Association between Constitutive Heterochromatin Polymorphism and Human Leukemias

Objective: polymorphism of the size of heterochromatin region ofchromosomes has been well documented in human genome and itconsists of dna sequences that are not transcribed. the prime aim ofthe present study was to evaluate the heterochromatin polymorphismassociated with chromosomes in leukemic patients.materials and methods: the study was conducted on 35 consecutiveleukemic patients and 34 healthy individuals in modaress and taleghanihospitals, tehran, iran between 2004-2006. by applying bariumhydroxide saline giemsa (bsc) method with certain alterations, thevariant heterochromatin polymorphism of chromosomes 1, 9 and 16 onbone marrow and peripheral blood lymphocyte cultures were evaluated.chi-square and fisher's exact tests were used for statistical analysiswith spss software.results: constitutive heterochromatin polymorphism of chromosomes1 and 9 in leukemic patients revealed statistical significant differenceswhen compared with chromosomes of healthy controls (p=0.0005)and (p=0.006) respectively. the differences were not significant forchromosome 16, it was 11.4% in leukemic patients and 0% in the controlgroup (p=0.05). the frequency of partial and complete inversions didnot show any significant differences between the leukemic patients andthe control group.conclusion: the constitutive heterochromatin polymorphism blocksmay provide an opportunity to serve as a marker for the detection andcharacterization of the chromosomes in leukemic patients.