非对称空间结构可以加速或减慢中性进化的分子钟
The molecular clock of neutral evolution can be accelerated or slowed by asymmetric spatial structure
摘要：
随着时间的推移，一个种群由于随机漂移而获得中性的基因替换。群体遗传学中一个著名的结果是，这些取代在群体中积累的速率$K$与它们在个体中出现的突变率$u$一致：$K=u$。这种同一性使基因序列数据能够被用作“分子钟”来估计进化事件的时间。虽然已知分子钟会受到选择的干扰，但人们认为$K=u$在中性进化中非常普遍。在这里，我们表明，不对称的空间种群结构可以改变中性突变的分子时钟速率，导致$K<u$或$K>u$。与$K=u$的偏离是因为突变在不同位点出现的不均匀性，并且根据它们出现的位置具有不同的固定概率。如果各研究中心的出生率相同，则为$K \leq u$。通常，$K$可以取0和$Nu$之间的任何值。我们的模型可以应用于各种人口结构。在一个例子中，我们研究了小肠〈动〉<动>中基因突变的积累。在另一个应用中，我们分析了900多个Twitter网络，以研究网络拓扑结构对社会进化中中性创新固定的影响。
英文摘要：
Over time, a population acquires neutral genetic substitutions as a consequence of random drift. A famous result in population genetics asserts that the rate, $K$, at which these substitutions accumulate in the population coincides with the mutation rate, $u$, at which they arise in individuals: $K=u$. This identity enables genetic sequence data to be used as a "molecular clock" to estimate the timing of evolutionary events. While the molecular clock is known to be perturbed by selection, it is thought that $K=u$ holds very generally for neutral evolution. Here we show that asymmetric spatial population structure can alter the molecular clock rate for neutral mutations, leading to either $K<u$ or $K>u$. Deviations from $K=u$ occur because mutations arise unequally at different sites and have different probabilities of fixation depending on where they arise. If birth rates are uniform across sites, then $K \leq u$. In general, $K$ can take any value between 0 and $Nu$. Our model can be applied to a variety of population structures. In one example, we investigate the accumulation of genetic mutations in the small intestine. In another application, we analyze over 900 Twitter networks to study the effect of network topology on the fixation of neutral innovations in social evolution.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
