In 1963, Margoliash discovered the unexpected genetic equidistance result after comparing cytochrome c sequences from different species. This finding, together with the hemoglobin analyses of Zuckerkandl and Pauling in 1962, directly inspired the ad hoc molecular clock hypothesis. Unfortunately, however, many biologists have since mistakenly viewed the molecular clock as a genuine reality, which in turn inspired Kimura, King, and Jukes to propose the neutral theory of molecular evolution. Many years of studies have found numerous contradictions to the theory, and few today believe in a universal constant clock. What is being neglected, however, is that the failure of the molecular clock hypothesis has left the original equidistance result an unsolved mystery. In recent years, we fortuitously rediscovered the equidistance result, which remains unknown to nearly all researchers. Incorporating the proven virtues of existing evolutionary theories and introducing the novel concept of maximum genetic diversity, we proposed a more complete hypothesis of evolutionary genetics and reinterpreted the equidistance result and other major evolutionary phenomena. The hypothesis may rewrite molecular phylogeny and population genetics and solve major biomedical problems that challenge the existing framework of evolutionary biology. genetic equidistance, overlap feature, evolution, molecular clock, neutral theory, maximum genetic diversity hypothesis, microevolution, macroevolution
Citation:Hu T B, Long M P, Yuan D J, et al. The genetic equidistance result: misreading by the molecular clock and neutral theory and reinterpretation nearly half of a century later. Sci China Life Sci, 2013Sci, , 56: 254 -261, doi: 10.1007 Among the most interesting phenomena in biology are reproduction, heredity, and evolution. Biological evolution includes both phenotypes and molecules, which are modeled by the theory of natural selection and the neutral theory, respectively. Together, the two make up the modern evolutionary theory (MET). The neutral theory was proposed by Kimura, Jukes, and King to explain the observation that molecules evolved at a steady, clock-like rate [1,2]. But is the molecular clock a genuine universal phenomenon?1 A brief history of the molecular clock hypothesis and the neutral theory: how the molecular clock replaced the genetic equidistance phenomenonGenetic distance is a measure of molecular differences between species and is represented by the percentage differ-