CHROMOSOMAL TRANSLOCATION IN APL

APL is caused by a translocation between chromosomes 15 and 17. Part of chromosome 15 is translocated to 17 and vice versa. This cross-over happens between the genes PML and RARα, resulting in a fusion protein of the two.

Both RAR and PML induce genes important for differentiation of a promyelocyte into a granulocyte. PML-RARα fusion protein hinders normal transcription of PML and RARα regulated genes.