PROBLEM TO BE SOLVED: To obtain the subject new gene as a causative gene of Werner diseases useful for manufacturing a medicine for detecting the cause of a disease such as sterilitas and remitting the disease. SOLUTION: Gene WS-2 codes a polypeptide substantially containing an amino acid sequence of formula I or an amino acid sequence of formula II as its variant sequence. A coding map of a gene domain (WS domain) is formed by a position cloning method and detection of cDNA and determination of a base sequence is carried out by using a cloned PI/PAC DNA constituting the map to obtain a new gene WS-2.