Structure

Single-stranded DNA or RNA molecule.

Double-stranded RNA molecule with a guide strand and a passenger strand.

Mechanism of Action

Binds to target RNA through complementary base pairing, modulating gene expression via RNase H activation or steric hindrance.

Binds perfectly complementary RNA, inducing target mRNA cleavage via the RISC complex.

Delivery

Delivered as single molecules; typically conjugated with ligands like GalNAc for targeted delivery.

Delivered as duplex RNA; often formulated with nanoparticles or lipid-based carriers.

Target Specificity

Can target both pre-mRNA (splicing modulation) and mature mRNA.

Targets mature mRNA only due to its mechanism requiring perfect complementarity.

Applications

Splicing modulation, gene knockdown, and disease-specific RNA regulation.

Gene silencing through degradation of specific mRNA.

Stability

Chemically modified for increased nuclease resistance and longer half-life.

Less stable due to inherent susceptibility to nuclease degradation.

Tissue Targeting

Can be targeted to specific tissues, such as liver or CNS, via chemical conjugates.

Typically relies on delivery systems for effective tissue targeting.

Examples

Nusinersen, Mipomersen, Eteplirsen.

ONPATTRO (Patisiran), GIVLAARI (Givosiran).