School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA.
Genome Biol Evol. 2024 May 2;16(5). doi: 10.1093/gbe/evae111.
Lengths of telomeres vary by an order of magnitude across mammalian species. Similarly, age- and sex-standardized telomere lengths differ by up to 1 kb (14%) across human populations. How to explain these differences? Telomeres play a central role in senescence and aging, and genes that affect telomere length are likely under weak selection (i.e. telomere length is a trait that is subject to nearly neutral evolution). Importantly, natural selection is more effective in large populations than in small populations. Here, we propose that observed differences in telomere length across species and populations are largely due to differences in effective population sizes. In this perspective, we present preliminary evolutionary genetic evidence supporting this hypothesis and highlight the need for more data.
端粒的长度在哺乳动物物种之间差异可达一个数量级。同样，在人类群体中，经过年龄和性别标准化的端粒长度差异可达 1kb（14%）。如何解释这些差异？端粒在衰老和老化中起着核心作用，影响端粒长度的基因可能受到弱选择（即端粒长度是一个几乎处于中性进化的特征）的影响。重要的是，自然选择在大群体中比在小群体中更有效。在这里，我们提出，在物种和种群之间观察到的端粒长度差异主要是由于有效种群大小的差异造成的。在这个观点中，我们提出了初步的进化遗传证据来支持这一假设，并强调需要更多的数据。
