Evolution of the stem cell population responsible for homeostatic cell renewal processes is analyzed. We assume that this regime is the product of a delicate balance between symmetric divisions that, after each cell cycle, originates a new stem cell or its disappearance (through cell differentiation). This dynamics leads to a monoclonal population, that is for an initial homogeneous set of stem cells, fixation of each clone is equiprobable. In this work we show that if there is an altered stem cell with a longer cell cycle than the rest, the fixation of this altered clone is more likely. We also study the consequeces of the appearance of successive alterations with these characteristics and their fixations. This effect is purely due to inherent characteristics of the cell renewal dynamics and as time goes by it leads to a quiescence state for stem cells owing to the recurrent fixation of such altered cells. Therefore it would contribute to the aging process.

中文翻译：

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随机细胞更新过程和细胞周期延长。

分析了负责稳态细胞更新过程的干细胞群体的进化。我们假设这种机制是对称分裂之间微妙平衡的产物，在每个细胞周期之后，对称分裂产生一个新的干细胞或其消失（通过细胞分化）。这种动力学导致了一个单克隆种群，即对于最初的同质干细胞集合，每个克隆的固定都是等价的。在这项工作中，我们表明，如果干细胞发生改变，而细胞周期比其他细胞更长，那么这种发生改变的克隆更可能被固定。我们还研究了具有这些特征及其固定方式的连续变化的后遗症。这种作用纯粹是由于细胞更新动力学的固有特性，随着时间的流逝，由于这种改变的细胞的反复固定，导致干细胞进入静止状态。因此，它将有助于老化过程。