SNPs and millions of small variations in the human genome

By: James V. Kohl | Published on: November 10, 2014

Thousands of never-before-seen human genome variations uncovered

Excerpt: “This approach has successfully pinpointed millions of small variations in the human genome. These variations arise from substitution of a single nucleotide base, called a single-nucleotide polymorphisms or SNP.”
My comment: In the mouse-to-human model of nutrient-dependent RNA-mediated amino acid substitutions and cell type differentiation, one SNP is linked to one amino acid substitution and many different cell types in different tissues of different organs in different organ systems in mice and humans via the same gene, cell, tissue, organ, organ-system pathway.
See for example: Nutrient-dependent/pheromone-controlled adaptive evolution: a model.
Excerpt: “This synergy requires at least two things to happen simultaneously: for example, (1) natural selection for nutrient chemicals and (2) sexual selection for odor production. Sexual selection for nutrient-dependent odor production is not likely to be achieved via one mutation involved in nutrient acquisition and another mutation that is involved in odor production because two mutations are not likely to simultaneously occur.”

See also: Human uniqueness: genome interactions with environment, behaviour and culture

Excerpt: “Although Wallace was criticized for apparently invoking spiritual explanations192, one of his key points remains valid — that it is difficult to explain how conventional natural selection could have selected ahead of time for the remarkable capabilities of the human mind, which we are still continuing to explore today.”
My comment: The GnRH neuronal system regulates the nutrient-dependent pheromone-controlled differentiation of cell types in all vertebrates. Controlled cell type differentiation explains why natural selection of food was required for development of ecological, social, neurogenic, and socio-cognitive niche construction during the increasing organismal complexity that led to the remarkable capabilities of the human mind.
Evolution of gonadotropin-releasing hormone (GnRH) structure and its receptor
Excerpt 1) “…the surprising total conservation of GnRH II’s primary structure, from bony fish to man, appears to be a result of the excellent coordinated evolutionary selection of amino acids participating in binding, activation and configuration such that its structure cannot be improved by substitution with any natural amino acid at any position.”
Excerpt 2) “It is possible that GnRH has an early origin in life history as a regulator of reproduction, since yeast α mating factor has 80% amino acid homology with mammalian GnRH and stimulates gonadotropin release from the mammalian pituitary (Loumaye et al., 1982; King and Millar, 1995).”
Conclusion: “The discovery of the fact that one decapeptide molecule, among the GnRHs, was constructed perfectly at the beginning of 400 million years evolution and that it is not possible to improve its physiological potency using the any natural amino acid is, in my opinion, important, fascinating and beautiful.”
My comment: Perfect construction of one molecule that links nutrient-dependent pheromone-controlled reproduction via conserved molecular mechanisms in species from microbes to man via amino acid substitutions does not suggest that evolution has occurred via mutations or via natural selection for anything except food. That takes us back to Wallace, who invoked spiritual explanations,  and back to Darwin, who put his ‘conditions of life’ before natural selection.
Nutrient-dependent ‘conditions of life’ and nutrient-dependent RNA-directed DNA methylation link amino acid substitutions and cell type differentiation to Dobzhansky (1973): Nothing in Biology Makes Any Sense Except in the Light of Evolution. “…the so-called alpha chains of hemoglobin have identical sequences of amino acids in man and the chimpanzee, but they differ in a single amino acid (out of 141) in the gorilla.”
1) Is there a way to link SNPs to genetic variation without RNA-mediated amino acid substitutions?
2) Is there a way to link genetic variation to chromosomal rearrangements without the pheromone-controlled physiology of reproduction?
If the answer is no to both those questions, Wallace’s spiritual explanations can be validated in the context of Darwin’s ‘conditions of life’. The never-before-seen human genome variations can then be placed into the context of odor-induced de novo creation of olfactory receptor genes that link the epigenetic landscape to the physical landscape of DNA in species from microbes to man via conserved molecular mechanisms of RNA-mediated cell type differentiation.
Alternatively, we can expect the Eichler lab to continue promoting their view that “Genomic duplication followed by adaptive mutation is considered one of the primary forces for evolution of new gene function.


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