Background and Objective: Philadelphia
chromosome is the chromosome originating from the
reciprocal translocation between long arms of
chromosome 9 and chromosome 22 t (9;22) (q34;
q11), it presents in 90 - 95% of patients with chronic
myeloid leukemia. The aberration results from a
reciprocal translocation are creating a BCR-ABL fusion
gene. There are two major forms of the BCR-ABL fusion
gene, involving ABL exon 2, but including different
exons of BCR gene. The transcript b3a2 and b2a2
codes for a p210 protein. Other fusion gene leads to
the expression of an e1a2 transcript, which codes for
a p190 protein. Its frequency varies in different
populations but there are no data from northeastern
Thailand. In this study we aimed to report BCR-ABL
fusion transcript types in northeastern Thailand CML
patients by Multiple Reverse Transcriptase-Polymerase
Chain Reaction (Multiplex PCR).
Materials and Methods Retrospective descriptive and
analytical study of all adult CML patients in Srinagarind
and Khon Kaen hospitals, which is the main tertiary
medical center in the northeastern region Thailand.
Data has been collected from medical records for 3
years (January 2017 to January 2020). Peripheral
blood or bone marrow samples were analyzed by
multiplex PCR from 177 adult northeastern Thailand
CML patients. Aim to identify BCR-ABL fusion transcript
types in northeastern Thailand CML patients. Multiplex PCR.
Results: All patients examined were positive for some
type of BCR/ABL rearrangement. The majority of the
patients (93.79%) expressed one of the p210 BCR-ABL
transcripts, b3a2 and b2a2 transcript types were
detected in 58.19% and 35.59% respectively.
Co-expression of b3a2 (p210)/e1a2 (p230) was
detected in 0.56%. The expression of an e1a2
transcript type, which codes for a p190 protein showed
4.52%. And 1.14% was detected in e19a2 transcript
type. Co-expression of p210/p190 was not detected.
Conclusions: Multiplex RT-PCR is useful and saves
time in the detection of BCR-ABL fusion transcript
types; the occurrence of these transcripts associated
with CML can assist in prognosis and treatment of
disease.