PROBLEM TO BE SOLVED: To provide a method for inducing chromosome breakage in an insect reduction division stage, and to provide a DNA used for the method. SOLUTION: A fused protein of a Ga14DNA bound domain (Ga14BD) with a fruit fly reduction division recombination start enzyme (DmSpoll) has been used to develop a method for inducing a specific chromosome breakage in a reduction division stage in an insect such as the fruit fly. By the method of the present invention, a homologous recombination can efficiently be induced. The method of the present invention is a method characterized in that the reduction division recombination is caused only in oocyte, and a non-homogenous recombination enzyme is not expressed therein. COPYRIGHT: (C)2008,JPO&INPIT