De Novo Origin of Human Protein-Coding Genes
Dong-Dong Wu1, David M. Irwin1,2,3, Ya-Ping Zhang1,4*
1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China, 2 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada, 3 Banting and Best Diabetes Centre, University of Toronto, Toronto, Canada, 4 Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, China
Abstract
The de novo origin of a new protein-coding gene from non-coding DNA is considered to be a very rare occurrence in genomes. Here we identify 60 new protein-coding genes that originated de novo on the human lineage since divergence from the chimpanzee. The functionality of these genes is supported by both transcriptional and proteomic evidence. RNA–seq data indicate that these genes have their highest expression levels in the cerebral cortex and testes, which might suggest that these genes contribute to phenotypic traits that are unique to humans, such as improved cognitive ability. Our results are inconsistent with the traditional view that the de novo origin of new genes is very rare, thus there should be greater appreciation of the importance of the de novo origination of genes.
Author Summary
The origin of genes can involve mechanisms such as gene duplication, exon shuffling, retroposition, mobile elements, lateral gene transfer, gene fusion/fission, and de novo origination. However, de novo origin, which means genes originate from a non-coding DNA region, is considered to be a very rare occurrence. Here we identify 60 new protein-coding genes that originated de novo on the human lineage since divergence from the chimpanzee, supported by both transcriptional and proteomic evidence. It is inconsistent with the traditional view that the de novo origin of new genes is rare. RNA–seq data indicate that these de novo originated genes have their highest expression in the cerebral cortex and testes, suggesting these genes may contribute to phenotypic traits that are unique to humans, such as development of cognitive ability. Therefore, the importance of de novo origination needs greater appreciation.
Citation: Wu D-D, Irwin DM, Zhang Y-P (2011) De Novo Origin of Human Protein-Coding Genes. PLoS Genet 7(11): e1002379. doi:10.1371/journal.pgen.1002379
Editor: David J. Begun, University of California Davis, United States of America
Received: May 10, 2011; Accepted: September 21, 2011; Published: November 10, 2011
Copyright: © 2011 Wu et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: This work was supported by grants from the National Basic Research Program of China (973 Program, 2007CB411600), the National Natural Science Foundation of China, and the Bureau of Science and Technology of Yunnan Province. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
* E-mail: zhangyp@mail.kiz.ac.cn
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