Patent ID: 8859749

Claim:
A double-stranded siRNA molecule comprising a sense strand and an antisense strand which is essentially complementary to the sense strand, each of the sense and the antisense strands comprising a core of at least 17 nucleotides (nt), the siRNA further comprising at least one overhang comprising one or more overhang residues at the 5′ and/or 3′ end of the sense and/or antisense strand, wherein at least one of the one or more overhang residues is chemically modified and comprises (a) a nucleotide modified at the 2′-position by a —O—CH 2 —O—(CH 2 ) 2 —OH group; or (b) a nucleotide comprising in the 3′-position a —CH 2 —O—(CH 2 ) 7 —CH 3 group.