Copy number variation (CNV) contributes to disease and has restructured the genomes of great apes. The diversity and rate of this process, however, have not been extensively explored among great ape lineages. We analyzed 97 deeply sequenced great ape and human genomes and estimate 16% (469 Mb) of the hominid genome has been affected by recent CNV. We identify a comprehensive set of fixed gene deletions (
n = 340) and duplications (
n = 405) as well as >13.5 Mb of sequence that has been specifically lost on the human lineage. We compared the diversity and rates of copy number and single nucleotide variation across the hominid phylogeny. We find that CNV diversity partially correlates with single nucleotide diversity (
r2 = 0.5) and recapitulates the phylogeny of apes with few exceptions. Duplications significantly outpace deletions (2.8-fold). The load of segregating duplications remains significantly higher in bonobos, Western chimpanzees, and Sumatran orangutans—populations that have experienced recent genetic bottlenecks (
P = 0.0014, 0.02, and 0.0088, respectively). The rate of fixed deletion has been more clocklike with the exception of the chimpanzee lineage, where we observe a twofold increase in the chimpanzee–bonobo ancestor (
P = 4.79 × 10
−9) and increased deletion load among Western chimpanzees (
P = 0.002). The latter includes the first genomic disorder in a chimpanzee with features resembling Smith-Magenis syndrome mediated by a chimpanzee-specific increase in segmental duplication complexity. We hypothesize that demographic effects, such as bottlenecks, have contributed to larger and more gene-rich segments being deleted in the chimpanzee lineage and that this effect, more generally, may account for episodic bursts in CNV during hominid evolution.Sequence and assembly of great ape reference genomes have consistently revealed that copy number variation (CNV) affects more base pairs than single nucleotide variation (SNV) (
Cheng et al. 2005;
The Chimpanzee Sequencing and Analysis Consortium 2005;
Locke et al. 2011). Segmental duplications, in particular, have disproportionately affected the African great ape (human, chimpanzee, and gorilla) lineages, where they appear to have accumulated at an accelerated rate (
Cheng et al. 2005;
Marques-Bonet et al. 2009). This has led to speculation that differences in fixation and copy number polymorphism may have contributed to the phenotypic “plasticity” and species-specific differences between humans and great apes (
Olson 1999;
Varki et al. 2008). While there is some evidence that fixed deletions and duplications contribute to morphological differences between humans and great apes (
McLean et al. 2011;
Charrier et al. 2012;
Dennis et al. 2012), a comprehensive assessment of these differences at the level of the genome has not yet been performed. Previous studies of CNV have been predominated by array comparative genomic hybridization (CGH) experiments (
Fortna et al. 2004;
Perry et al. 2006;
Dumas et al. 2007;
Gazave et al. 2011;
Locke et al. 2011), which provide limited size resolution, are imprecise in absolute copy number differences, and are biased by probes derived from the human reference genome. Comparisons of reference genomes have been complicated by assessments of a single individual and distinguishing CNVs from assembly errors (
The Chimpanzee Sequencing and Analysis Consortium 2005;
Locke et al. 2011;
Ventura et al. 2011;
Prüfer et al. 2012). Here, we compare the evolution and diversity of deletions, duplications, and SNVs in 97 great ape individuals sequenced to high coverage (median ∼25×)
(Prado-Martinez et al. 2013). The set includes multiple individuals from the four great ape genera, including Bornean and Sumatran orangutans, each of the four recognized chimpanzee subspecies, bonobos, and both Eastern and Western gorillas, in addition to 10 diverse humans and a high-coverage archaic Denisovan individual. This data set provides unprecedented genome-wide resolution to interrogate multiple forms of genetic variation and a unique opportunity to directly compare mutational processes and patterns of diversity in great apes.
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