International joint research led by Akihisa Osakabe and Yoshimasa Takizawa of the University of Tokyo has clarified the molecular mechanisms in thale cresses (Arabidopsis thaliana) by which the DDM1 (Decreased in DNA Methylation 1) protein prevents the transcription of ‘jumping genes.’ DDM1 makes ‘jumping genes’ more accessible for transcription-suppressing chemical marks to be deposited. Because a variant of this protein exists in humans, the discovery provides insight into genetic conditions caused by such ‘jumping gene’ mutations.