The present invention is a double-stranded nucleic acid consisting of a sense strand nucleic acid and an antisense strand nucleic acid, comprising a double-stranded region of at least 11 base pairs, wherein the antisense strand nucleic acid has at least 17 nucleotides and An oligonucleotide chain having a length of at most 30 nucleotides, which is complementary to the target APCS mRNA sequence containing the nucleotide sequence represented by any of SEQ ID NOs: 1288 to 1930, which suppresses the expression of the APCS gene. A strand nucleic acid is provided.本発明は、センス鎖核酸及びアンチセンス鎖核酸からなり、少なくとも11個の塩基対の二重鎖領域を含む二本鎖核酸であって、前記アンチセンス鎖核酸中の、少なくとも17個のヌクレオチドかつ多くとも30個のヌクレオチドの鎖長のオリゴヌクレオチド鎖において、配列番号１２８８～１９３０のいずれかで表される塩基配列を含む標的APCS mRNA配列と相補的である、APCS遺伝子の発現を抑制させる二本鎖核酸、を提供する。
