The key role of genome instability in tumorigenesis and a number of rare cancer-prone genetic diseases, as well as its potential risks in stem cell–based therapies, has made it a major subject in basic biological research, cancer biology and biomedicine. Our research goals are to identify and understand the causes and mechanisms of genome instability. They are based on the facts that eukaryotic DNA replication starts at multiple sites throughout the genome and is necessarily coordinated with transcription, sister chromatid cohesion, nucleosome assembly and cell cycle progression.