ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The loading of SiRNA was attempted by Valencia-Serna et al. using lipopolymers, namely, α-linolenic acid (ALA) substitution on low molecular weight polyethyleneimine (PEI) to deliver specific siRNAs to CML cells for therapeutic gene silencing of BCR–ABL gene.