Genomes, primordial

Senapathy, P. (1994), Independent Birth of Organisms A New Theory that Distinct Organisms Arose Independently from the Primordial Pond, Showing that Evolutionary Theories Are Fundamentally Incorrect, Genome Press, Madison, NJ. 

Fig. 1. Dynamics of DNA methylation levels during mouse development. The methylation patterns of the oocyte and the rapidly demethylated after fertilization sperm create the combined methylation patterns in the early mouse zygote. During the first two to three cleavage divisions, the 5mC levels decrease further and stay low through the blastula stage. Post-implantation, the mouse embryo genome is methylated de novo the CpG islands remain mostly unmethylated. The primordial germ cells remain unmethylated. During gametogenesis specific parental (maternal or paternal) patterns of DNA methylation are established at imprinted loci (for further details see Refs. [13, 14]) (re-drawn from Ref [4]).

Fig. 12.2. This is a take-ofF on a figure by paleontologists concerning the evolution of nonhuman primates and hominids. The worldlines of species from the Genomic Potential Hypothesis were added to the figure. Beginning in a circular region at the bottom which depicts a clonal relationship during primordial times, the species rise to the present or to extinction as relatives from a chemical pool as opposed to branches of a tree.

The accumulation of the primordial genome is a chance event by any hypothesis whereby one must grant the possibility that there may have been a tendency to form a certain sequence faster than another, but that problem is left waiting until one knows how primordial condensation occurred. In any case, the genomist claims that all variations observed today are due to prebiotic events1 in contrast to the old model.2 Proteins would change continuously in the Darwinian system with survival as the only selective force. Proteins in this type of study come, for obvious reasons, exclusively from survivors. The testable aspect of the hypothesis is the proposal that functionally important amino acids remain constant in a protein and that functionally unimportant ones are subject to mutational replacement. 

Lee J, Inoue K, Ono R, Ogonuki N, Kohda T, Kaneko-Ishino T, Ogura A, Ishino F. Erasing genomic imprinting memory in mouse clone embryos produced from day 11.5 primordial germ cells. Development 2002 129 1807— 1817. 

In the words of Lancet and colleagues, a fundamentally different approach has envisaged primordial selfreplication as the collective property of ensembles of relatively simple molecules, interconnected by networks of mutually catalytic interactions. 38 The hereditary information in this case would be represented by the identity and concentration of its components. The term compositional genome has been used to describe this system, in which genetic information is not stored in a list, as in DNA, but is represented by the presence or absence of organic components.39,40 As an analogy, consider DNA to be the equivalent of a class list that records the full possible enrollment in a course. The information in a compositional genome would be represented by the presence of students who have turned up on a particular day. 

The primordial cellular genomes consisted of competing and cooperating RNA/DNA complexes. These ancient faculties of cooperation and competition remain preserved up to the present time. While DNA commands the genome, RNA remains the mler of the epigenome. However, the RNAs of the spliceosomes begin their actions in the nucleus. MicroRNAs buzz all over the epigenome and in the cytoplasm. 

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