The Ph chromosome is formed by a reciprocal
t(9;22)(q34;q11) translocation between the long arms of chromosomes
9 and 22, causing the juxtaposition of the BCR and
ABL1 genes. The BCR-ABL1 fusion gene consists of the 5′
end of the BCR (breakpoint cluster region) gene and the 3′end
of the ABL1 gene (also known as Abelson)