The Chimpanzee Sequencing and Analysis Consortium presents a draft genome sequence of the common chimpanzee (Pan troglodytes) and compares it with the human genome. The comparison reveals approximately 35 million single-nucleotide changes, 5 million insertion/deletion events, and various chromosomal rearrangements since the divergence of humans and chimpanzees from their common ancestor. The study explores the magnitude and regional variation of mutational forces shaping these genomes and the strength of positive and negative selection acting on genes. Key findings include: - Single-nucleotide substitutions occur at a mean rate of 1.23% between human and chimpanzee genomes, with fixed divergence between the species being around 1.06%. - Regional variation in nucleotide substitution rates is conserved between hominids and murids, but subtelomeric regions show disproportionately elevated rates in hominids. - Substitutions at CpG dinucleotides occur at similar rates in male and female germ lines, suggesting balanced mutagenesis. - Insertion and deletion events are fewer than single-nucleotide substitutions but result in about 1.5% of euchromatic sequence being lineage-specific. - Transposable element insertions differ between humans and chimpanzees, with short interspersed elements (SINEs) being more active in humans and new retroviral elements being active in chimpanzees. The study also examines the evolution of protein-coding genes, finding that human and chimpanzee genes are extremely similar, with 29% of orthologous proteins identical. The analysis reveals that about 77% of amino acid alterations in hominid genes are sufficiently deleterious to be eliminated by natural selection. Additionally, the study identifies several loci as potential candidates for strong selective sweeps in recent human history.The Chimpanzee Sequencing and Analysis Consortium presents a draft genome sequence of the common chimpanzee (Pan troglodytes) and compares it with the human genome. The comparison reveals approximately 35 million single-nucleotide changes, 5 million insertion/deletion events, and various chromosomal rearrangements since the divergence of humans and chimpanzees from their common ancestor. The study explores the magnitude and regional variation of mutational forces shaping these genomes and the strength of positive and negative selection acting on genes. Key findings include: - Single-nucleotide substitutions occur at a mean rate of 1.23% between human and chimpanzee genomes, with fixed divergence between the species being around 1.06%. - Regional variation in nucleotide substitution rates is conserved between hominids and murids, but subtelomeric regions show disproportionately elevated rates in hominids. - Substitutions at CpG dinucleotides occur at similar rates in male and female germ lines, suggesting balanced mutagenesis. - Insertion and deletion events are fewer than single-nucleotide substitutions but result in about 1.5% of euchromatic sequence being lineage-specific. - Transposable element insertions differ between humans and chimpanzees, with short interspersed elements (SINEs) being more active in humans and new retroviral elements being active in chimpanzees. The study also examines the evolution of protein-coding genes, finding that human and chimpanzee genes are extremely similar, with 29% of orthologous proteins identical. The analysis reveals that about 77% of amino acid alterations in hominid genes are sufficiently deleterious to be eliminated by natural selection. Additionally, the study identifies several loci as potential candidates for strong selective sweeps in recent human history.