Identification by full-coverage array CGH of human DNA copy number increases relative to chimpanzee and gorilla - PubMed (original) (raw)

Comparative Study

Identification by full-coverage array CGH of human DNA copy number increases relative to chimpanzee and gorilla

Gary M Wilson et al. Genome Res. 2006 Feb.

Abstract

Duplication of chromosomal segments and associated genes is thought to be a primary mechanism for generating evolutionary novelty. By comparative genome hybridization using a full-coverage (tiling) human BAC array with 79-kb resolution, we have identified 63 chromosomal segments, ranging in size from 0.65 to 1.3 Mb, that have inferred copy number increases in human relative to chimpanzee. These segments span 192 Ensembl genes, including 82 gene duplicates (41 reciprocal best BLAST matches). Synonymous and nonsynonymous substitution rates across these pairs provide evidence for general conservation of the amino acid sequence, consistent with the maintenance of function of both copies, and one case of putative positive selection for an uncharacterized gene. Surprisingly, the core histone genes H2A, H2B, H3, and H4 have been duplicated in the human lineage since our split with chimpanzee. The observation of increased copy number of a human cluster of core histone genes suggests that altered dosage, even of highly constrained genes, may be an important evolutionary mechanism.

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Figures

Figure 1.

Figure 1.

Human chimpanzee DNA copy number ratio determined by full-coverage BAC array CGH.

Figure 2.

Figure 2.

Relative copy number of the AMY1A and CNTNAP3 loci in three unrelated chimpanzees and a single gorilla compared to a single pooled sample of human gDNA.

References

    1. Adams, R. and Bischof, L. 1994. Seeded region growing. IEEE Trans. Pattern Anal. Machine Intell. 16 641-647.
    1. Altschul, S.F., Madden, T.L., Schaffer, A.A., Zhang, J., Zhang, Z., Miller, W., and Lipman, D.J. 1997. Gapped BLAST and PSI-BLAST: A new generation of protein database search programs. Nucleic Acids Res. 25 3389-3402. - PMC - PubMed
    1. Bailey, J.A., Gu, Z., Clark, R.A., Reinert, K., Samonte, R.V., Schwartz, S., Adams, M.D., Myers, E.W., Li, P.W., and Eichler, E.E. 2002. Recent segmental duplications in the human genome. Science 297 1003-1007. - PubMed
    1. Chen, F.-C. and Li, W.-H. 2001. Genomic differences between humans and other hominoids and the effective population size of the common ancestor of humans and chimpanzees. Am. J. Hum. Genet. 68 444-456. - PMC - PubMed
    1. Chimpanzee Sequencing and Analysis Consortium. 2005. Initial sequence of the chimpanzee genome and comparison with the human genome. Nature 437 69-87. - PubMed

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