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Although the flood of cell biological knowledge rises relentlessly, many databases face an uncertain future. Unless funding for essential bioinformatic resources is set in stone, the next storm may wash away the foundation of future cell biology research.
Regions of metazoan genomes replicate at defined times within S phase. This observation suggests that replication origins fire with a defined timing pattern that remains the same from cycle to cycle. However, an alterative model based on the stochastic firing of origins may also explain replication timing. This model assumes varying origin efficiency instead of a strict origin-timing programme. Here, we discuss the evidence for both models.