As for purpose of this invention, there are times when the composition and the like in order to control the revelation of the target gene is offered. Arrangement of 15 - 30 bases which mRNA of the target gene continues (below, arranging X,) and the said arrangement it contains the liposome which encloses RNA which includes the arrangement of X and the complimentary base (below, making complimentary arrangement X,), arrangement together 1 - 90% of the sugar which connects to the base of X and complimentary arrangement X, is the ribose which is substituted with the decoration basis 2 in rank is the liposome which arrives in organization or the internal organs to which the said liposome includes the revelation region of the target gene, the composition and the like is offered.本発明の目的は、標的遺伝子の発現を抑制するための組成物等を提供することにある。標的遺伝子のmRNAの連続する15~30塩基の配列(以下、配列Xとする)および該配列Xと相補的な塩基の配列(以下、相補配列X’とする)を含むRNAを封入したリポソームを含有し、配列Xおよび相補配列X’の塩基に結合する糖のあわせて1~90%が、2’位において修飾基で置換されたリボースであり、該リポソームが標的遺伝子の発現部位を含む組織または臓器に到達するリポソームである、組成物等を提供する。
