Department of Biology, Centre for Applied Synthetic Biology, Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec H4B 1R6, Canada.
Department of Human Genetics, McGill University, Montreal, Quebec H3A 0C7, Canada.
Chaos. 2024 May 1;34(5). doi: 10.1063/5.0206011.
In the evolution of species, the karyotype changes with a timescale of tens to hundreds of thousand years. In the development of cancer, the karyotype often is modified in cancerous cells over the lifetime of an individual. Characterizing these changes and understanding the mechanisms leading to them has been of interest in a broad range of disciplines including evolution, cytogenetics, and cancer genetics. A central issue relates to the relative roles of random vs deterministic mechanisms in shaping the changes. Although it is possible that all changes result from random events followed by selection, many results point to other non-random factors that play a role in karyotype evolution. In cancer, chromosomal instability leads to characteristic changes in the karyotype, in which different individuals with a specific type of cancer display similar changes in karyotype structure over time. Statistical analyses of chromosome lengths in different species indicate that the length distribution of chromosomes is not consistent with models in which the lengths of chromosomes are random or evolve solely by simple random processes. A better understanding of the mechanisms underlying karyotype evolution should enable the development of quantitative theoretical models that combine the random and deterministic processes that can be compared to experimental determinations of the karyotype in diverse settings.
在物种进化过程中，染色体组会随着数十万年到数百年的时间尺度而发生变化。在癌症的发展过程中，染色体组通常会在个体的一生中发生改变。描述这些变化并理解导致这些变化的机制，是进化、细胞遗传学和癌症遗传学等多个领域都感兴趣的问题。一个核心问题涉及到随机机制和确定性机制在塑造这些变化方面的相对作用。虽然所有的变化都有可能是随机事件发生后经过选择的结果，但许多结果表明，其他非随机因素在染色体组进化中发挥了作用。在癌症中，染色体不稳定性导致了染色体组的特征性变化，不同患有特定类型癌症的个体随着时间的推移会显示出相似的染色体组结构变化。对不同物种中染色体长度的统计分析表明，染色体的长度分布与染色体长度是随机的或仅通过简单的随机过程进化的模型不一致。更好地理解染色体组进化的机制，应该能够开发出定量的理论模型，将随机过程和确定性过程结合起来，可以与不同环境下的染色体组的实验测定进行比较。
