A high-resolution map of human evolutionary constraint using 29 mammals

Broad Institute of Harvard and Massachusetts Institute of Technology, 7 Cambridge Center, Cambridge, Massachusetts 02142, USA.
Nature (Impact Factor: 41.46). 10/2011; 478(7370):476-82. DOI: 10.1038/nature10530
Source: PubMed


The comparison of related genomes has emerged as a powerful lens for genome interpretation. Here we report the sequencing and comparative analysis of 29 eutherian genomes. We confirm that at least 5.5% of the human genome has undergone purifying selection, and locate constrained elements covering ∼4.2% of the genome. We use evolutionary signatures and comparisons with experimental data sets to suggest candidate functions for ∼60% of constrained bases. These elements reveal a small number of new coding exons, candidate stop codon readthrough events and over 10,000 regions of overlapping synonymous constraint within protein-coding exons. We find 220 candidate RNA structural families, and nearly a million elements overlapping potential promoter, enhancer and insulator regions. We report specific amino acid residues that have undergone positive selection, 280,000 non-coding elements exapted from mobile elements and more than 1,000 primate- and human-accelerated elements. Overlap with disease-associated variants indicates that our findings will be relevant for studies of human biology, health and disease.

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    • "Fieldwork on E. helvum and E. du preanum was conducted under permits granted by national and local authorities. Research involving live animals followed guidelines for the capture, handling, and care of mammals approved by the American Society of Mammalogists (Sikes et al., 2011). FIG. 1. Map of sampling localities for E. helvum across sub-Saharan "
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