Hafeez Madiha, Shabbir Madiha, Altaf Fouzia, Abbasi Amir Ali
National Center for Bioinformatics, Program of Comparative and Evolutionary Genomics, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
National Center for Bioinformatics, Program of Comparative and Evolutionary Genomics, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
Mol Phylogenet Evol. 2016 Jan;94(Pt A):95-100. doi: 10.1016/j.ympev.2015.08.019. Epub 2015 Sep 2.
Evolution of organismal complexity and origin of novelties during vertebrate history has been widely explored in context of both regulation of gene expression and gene duplication events. Ohno (1970) for the first time put forward the idea of two rounds whole genome duplication events as the most plausible explanation for evolutionarizing the vertebrate lineage (2R hypothesis). To test the validity of 2R hypothesis, a robust phylogenomic analysis of multigene families with triplicated or quadruplicated representation on human FGFR bearing chromosomes (4/5/8/10) was performed. Topology comparison approach categorized members of 80 families into five distinct co-duplicated groups. Genes belonging to one co-duplicated group are duplicated concurrently, whereas genes of two different co-duplicated groups do not share their duplication history and have not duplicated in congruency. Our findings contradict the 2R model and are indicative of small-scale duplications and rearrangements that cover the entire span of animal's history.
在脊椎动物进化历程中，生物体复杂性的演变和新特征的起源，已在基因表达调控和基因复制事件的背景下得到广泛探讨。大野乾（1970年）首次提出两轮全基因组复制事件的观点，认为这是脊椎动物谱系进化（2R假说）最合理的解释。为验证2R假说的有效性，我们对人类FGFR相关染色体（4/5/8/10）上具有三倍或四倍拷贝的多基因家族进行了稳健的系统发育基因组分析。拓扑比较方法将80个家族的成员分为五个不同的共同复制组。属于同一共同复制组的基因是同时复制的，而两个不同共同复制组的基因没有共同的复制历史，也不是同步复制的。我们的研究结果与2R模型相矛盾，表明小规模的复制和重排贯穿了动物进化的整个历程。
