Genome-wide mapping of asynchronous replication in clonal mouse cells

The entire genome is divided into distinct 1-2 Mb zones that replicate in an ordered and coordinated manner during S phase. While most regions of the genome replicate both alleles in a synchronous manner, some loci have been found to replicate asynchronously, with one allele undergoing DNA synthesis early in S phase, with the other replicating during late S. Random asynchronous replication timing is characterized by cell heterogeneity with some cells. having the maternal allele early replicating while in others, the orientation is reversed, with the paternal allele being early. This type of asynchronous replication can only be studied in a clonal or single cell manner. We have used the repli-seq method to study pre-B clonal f1 mouse cells in order to identify and study asynchronous regions in a genome-wide manner. Overall design: Examination of replication timing in mouse pre-b cells for four clonal CAST/C57BL F1 samples (e5, clone 8, clone 3, clone 2) and one clonal CAST sample. Three replicates were performed for each sample.