siRNAs are known to have off-target effects, need transfection reagents, and do not work well in animal or fish models. They are expensive and need optimization. FANA oligos can be self-delivered without the use of any delivery agent. Further, as opposed to double-stranded siRNAs that use the RNAi pathway (involving RISC), FANAs are single-stranded next generation antisense oligonucleotides that use RNase H to mediate cleavage of the target. This mode is much simpler and does not have RISC-associated off-target effects. Lastly, FANA oligos can go into the nucleus and can be used to knockdown nuclear targets as well.