作者: Wesley M. Brown , Ellen M. Prager , Alice Wang , Allan C. Wilson
DOI: 10.1007/BF01734101
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摘要: We cloned and sequenced a segment of mitochondrial DNA from human, chimpanzee, gorilla, orangutan, gibbon. This is 896 bp in length, contains the genes for three transfer RNAs parts two proteins, homologous all 5 primates. The sequences differ one another by base substitutions at 283 positions deletion pair. sequence differences range 9 to 19% among species, agreement with estimates cleavage map comparisons, thus confirming that rate mtDNA evolution primates 10 times higher than nuclear DNA. most striking new finding emerge these comparisons transitions greatly outnumber transversions. Ninety-two percent closely related species (human, gorilla) are transitions. For pairs longer divergence times, observed percentage falls until, case between non-primates, it reaches value 45. time dependence probably due obliteration record multiple same nucleotide site. illustrates importance choosing analysis evolutionary process. remarkable bias toward necessitates revision equations correct With revised equations, we calculated incidence silent replacement protein-coding genes. substitution 4 6 rate, indicating strong functional constraints sites. Moreover, about 10% per million years, studied so far. In addition, mean tRNA least 100 Finally, genealogical supports view human lineage branched off only slightly before gorilla chimpanzee lineages diverged strengthens hypothesis humans more gorillas chimpanzees orangutan.