Wang et al. Genetics Selection Evolution 2010, 42:24 http://www.gsejournal.org/content/42/1/24 eukaryotic paralog/paralogon information. Nucleic Acids Res 2008:D255-262. 18. Smith JM, Smith NH: Synonymous nucleotide divergence: what is "saturation"? Genetics 1996, 142:1033-1036. 19. Su AI, Wiltshire T, Batalov S, Lapp H, Ching KA, Block D, Zhang J, Soden R, Hayakawa M, Kreiman G, Cooke MP, Walker JR, Hogenesch JB: A gene atlas of the mouse and human protein-encoding transcriptomes. Proc Natl Acad Sci USA 2004, 101:6062-6067. 20. Kondrashov FA, Koonin EV: A common framework for understanding the origin of genetic dominance and evolutionary fates of gene duplications. Trends Genet 2004, 20:287-290. 21. He X, Zhang J: Gene complexity and gene duplicability. Curr Biol 2005, 15:1016-1021. 22. He X, Zhang J: Higher duplicability of less important genes in yeast genomes. Mol Biol Evol 2006, 23:144-151. 23. Prachumwat A, Li WH: Protein function, connectivity, and duplicability in yeast. Mol Biol Evol 2006, 23:30-39. 24. Liang H, Li WH: Gene essentiality, gene duplicability and protein connectivity in human and mouse. Trends Genet 2007, 23:375-378. 25. Liao BY, Zhang J: Mouse duplicate genes are as essential as singletons. Trends Genet 2007, 23:378-381. 26. Zhang P, Gu Z, Li WH: Different evolutionary patterns between young duplicate genes in the human genome. Genome Biol 2003, 4:R56. 27. Davis JC, Petrov DA: Preferential duplication of conserved proteins in eukaryotic genomes. PLoS Biol 2004, 2:E55. 28. Gao LZ, Innan H: Very low gene duplication rate in the yeast genome. Science 2004, 306:1367-1370. 29. Li WH, Yang J, Gu X: Expression divergence between duplicate genes. Trends Genet 2005, 21:602-607. 30. Gu Z, Nicolae D, Lu HH, Li WH: Rapid divergence in expression between duplicate genes inferred from microarray data. Trends Genet 2002, 18:609-613. 31. Gu Z, Rifkin SA, White KP, Li WH: Duplicate genes increase gene expression diversity within and between species. Nat Genet 2004, 36:577-579. 32. Lynch M, Conery JS: The origins of genome complexity. Science 2003, 302:1401-1404. 33. Shiu SH, Byrnes JK, Pan R, Zhang P, Li WH: Role of positive selection in the retention of duplicate genes in mammalian genomes. Proc Natl Acad Sci USA 2006, 103:2232-2236. 34. Gu Z, Steinmetz LM, Gu X, Scharfe C, Davis RW, Li WH: Role of duplicate genes in genetic robustness against mutations. Nature 2003, 421:63-66. 35. Redon R, Ishikawa S, Fitch KR, Feuk L, Perry GH, Andrews TD, Fiegler H, Shapero MH, Carson AR, Chen W, Cho EK, Dallaire S, Freeman JL, Gonzalez JR, Gratacos M, Huang J, Kalaitzopoulos D, Komura D, MacDonald JR, Marshall CR, Mei R, Montgomery L, Nishimura K, Okamura K, Shen F, Somerville MJ, Tchinda J, Valsesia A, Woodwark C, Yang F: Global variation in copy number in the human genome. Nature 2006, 444:444-454. 36. Nguyen DQ, Webber C, Ponting CP: Bias of selection on human copy- number variants. PLoS Genet 2006, 2:e20. 37. Storz JF: Genome evolution: gene duplication and the resolution of adaptive conflict. Heredity 2009, 102:99-100. 38. Force A, Lynch M, Pickett FB, Amores A, Yan YL, Postlethwait J: Preservation of duplicate genes by complementary, degenerative mutations. Genetics 1999, 151:1531-1545. 39. Vinckenbosch N, Dupanloup I, Kaessmann H: Evolutionary fate of retroposed gene copies in the human genome. Proc Natl Acad Sci USA 2006, 103:3220-3225. doi: 10.1186/1297-9686-42-24 Cite this article as: Wang et al., Comparing the retention mechanisms of tandem duplicates and retrogenes in human and mouse genomes Genetics Selection Evolution 2010, 42:24 Page 6 of 6