Not sure how readily available this is yet, but thought I would share it. Would be great if they could include this test for everyone when first diagnosed or first sign of resistance to determine if T315I is involved
BCR-ABL kinase domain (KD) mutation is the major mechanism contributing to suboptimal response to tyrosine kinase inhibitors (TKI) in BCR-ABL-positive chronic myeloid leukemia (CML) patients. T315I mutation, as one of the most frequent KD mutations, has been shown to be strongly associated with TKI resistance and subsequent therapeutic failure.
A simple and sensitive method is thus required to detect T315I mutation at the earliest stage.
Methods: A single-tube allele specific-polymerase chain reaction (AS-PCR) method was developed to detect T315I mutation in a mixture of normal and mutant alleles of varying dilutions. Denaturing high performance liquid chromatography (DHPLC) and direct sequencing were performed as a comparison to AS-PCR.
Results: T315I mutant bands were observed in the mixtures containing as low as 0.5-1% of mutant alleles by AS-PCR.
The detection sensitivity of DHPLC was around 1.5-3% dilution whereas sequencing analysis was unable to detect below 6.25% dilution.
Conclusion: A single-tube AS-PCR is a rapid and sensitive screening method for T315I mutation. Detection of the most resistant leukemic clone in CML patients undergoing TKI therapy should be feasible with this simple and inexpensive method.
Author: Wanwisa WongboonmaWanna ThongnoppakhunChirayu Auewarakul
Credits/Source: Journal of Hematology &Oncology 2011, 4:7