An object of the present invention is to provide a nucleic acid expected to be useful for the treatment of dust mite allergy. The present invention provides a nucleic acid, which sequentially comprises a base sequence encoding a message peptide, a base sequence encoding a stable region in an organelle of LAMP, and a sequence encoding a base including Der p 1, Der p 2, Der p 23, and Der p 7. A base sequence of an allergen region, a base sequence encoding a transmembrane region, and a base sequence encoding an endosome / lysosomal target region of LAMP, and includes a base sequence encoding a chimeric protein.本發明之課題在於提供一種期待對塵蟎過敏治療有用之核酸。本發明提供一種核酸，其係依序包含編碼訊息肽之鹼基序列、編碼LAMP之胞器內穩定區之鹼基序列、編碼包含Der p 1、Der p 2、Der p 23及Der p 7之過敏原區之鹼基序列、編碼跨膜區之鹼基序列、以及編碼LAMP之內體/溶酶體靶區之鹼基序列者，且包含編碼嵌合體蛋白之鹼基序列。
