How to create for identifying expressed genes cDNA tag, and gene expression analysis method

The present invention relates to a method of creating for identifying expressed genes cDNA tag, and provides gene expression analysis method. One type II restriction enzyme, two kinds of type IIS restriction enzyme, two kinds of cDNA for identifying expressed genes by combining a linker X and Y containing the recognition sequence of one enzyme of the 2 kinds of type IIS restriction enzymes to create a tag. To obtain a consolidated body is carried out directly or coupling step, etc. The cDNA tag, it is possible to perform analysis of expressed genes.