Scientists lay foundation for single-cell level understanding of DNA replication

A research team has established a novel method to scrutinize DNA replication in individual cells. This method allowed them to obtain a detailed genome-wide view of replicated and unreplicated sequence distribution in each cell. They also succeeded in discriminating paternally and maternally derived homologous chromosomes in each cell by utilizing single-nucleotide variations between parents, making it possible to successfully visualize how each chromosome in the cell is replicated.
In all living organisms, proliferating cells go through the fundamental process of DNA replication. Through this process, they faithfully duplicate their DNA and divide into two daughter cells. In eukaryotes, the genomic DNA is replicated during the S-phase of the cell cycle, and the order of the replication—DNA replication timing—is known to be strongly correlated with the higher-order structure of chromatin—the structure through which DNA is folded. Hence, studying DNA replication is important for understanding not only the faithful maintenance of the genome but also its higher-order structure.