Manufacture or use of a mutant prenyl diphosphate synthase in which the amino acid residue located at the fifth position in the N-terminal direction from D of the N-terminal of the aspartic acid-rich domain DDXX(XX)D (the two X's in the parentheses may not be present) present in the second region among the conserved regions of the prenyl diphosphate synthase has been substituted by another amino acid.
