Silberman Institute of Life Sciences, Hebrew University, 91904, Jerusalem, Israel.
Bioinformatics Department, Jerusalem College of Technology, Tal Campus, Beit HaDfus 7, 95483, Jerusalem, Israel.
BMC Genomics. 2021 Nov 4;22(1):794. doi: 10.1186/s12864-021-08066-3.
The present availability of full genome sequences of a broad range of animal species across the whole range of evolutionary history enables one to ask questions as to the distribution of genes across the chromosomes. Do newly recruited genes, as new clades emerge, distribute at random or at non-random locations?
We extracted values for the ages of the human genes and for their current chromosome locations, from published sources. A quantitative analysis showed that the distribution of newly-added genes among and within the chromosomes appears to be increasingly non-random if one observes animals along the evolutionary series from the precursors of the tetrapoda through to the great apes, whereas the oldest genes are randomly distributed.
Randomization will result from chromosome evolution, but less and less time is available for this process as evolution proceeds. Much of the bunching of recently-added genes arises from new gene formation as paralogues in gene families, near the location of genes that were recruited in the preceding phylostratum. As examples we cite the KRTAP, ZNF, OR and some minor gene families. We show that bunching can also result from the evolution of the chromosomes themselves when, as for the KRTAP genes, blocks of genes that had previously been on disparate chromosomes become linked together.
目前，广泛的动物物种的全基因组序列在整个进化历史范围内都可获得，这使得人们能够提出关于基因在染色体上分布的问题。随着新的进化枝的出现，新招募的基因是随机分布还是非随机分布？
我们从已发表的资料中提取了人类基因的年龄及其当前染色体位置的值。定量分析表明，如果沿着从四足动物的祖先到类人猿的进化系列观察动物，新添加的基因在染色体之间和染色体内部的分布似乎越来越非随机，而最古老的基因则是随机分布的。
随机化将来自于染色体进化，但随着进化的进行，这个过程的可用时间越来越少。最近添加的基因簇集的大部分是由于基因家族中的新基因形成的同源基因，这些基因簇集靠近在前一个进化阶段招募的基因的位置。我们以 KRTAP、ZNF、OR 和一些较小的基因家族为例。我们还表明，当像 KRTAP 基因一样，以前位于不同染色体上的基因块连接在一起时，染色体本身的进化也会导致基因簇集。
