 PCR was performed with these primer sets by using PCR template of cDNA prepared from poly A+ RNA of various tissues of human origin, and more than 00 PCR products from each tissue were subcloned, as well as performing sequencing for more than 000 types. A clone having a desired sequence could be identified. Namely, the obtained PCR product is cloned in the cloning vector, transforming the host cells by using recombinant plasmid which contains the PCR product, culturing the host cells containing the recombinant plasmid on a large scale, purifying and isolating the recombinant plasmid, checking the DNA sequence of PCR product which is inserted into the cloning vector, and trying to obtain the gene fragment which may have a sequence of human 