A novel methodology that facilitates specific silencing of genes has recently been developed. The method is based on the property of small molecules of nucleic acids (RNA) to specifically repress expression of targeted genes. These small interfering RNA (siRNA) molecules were recently demonstrated to repress, in tissue culture cells, one of the two types of the common fusion genes present in CML patients. Those studies showed that treatment with synthetic siRNA inhibited cell growth and increased the sensitivity to imatinib. These findings offer hope that a novel form of gene therapy based on this strategy may improve the treatment outcome of CML patients, particularly when used in combination with other approaches such as the tyrosine kinase inhibitor imatinib that was mentioned above.