DNA

Molecular Structure of Nucleic Acids (1953) (r)
The famous 1953 article "Molecular Structure of Nucleic Acid" by James Watson and Francis Crick that introduced the world to DNA in name and structure. [5]
In science, DNA, an acronym of deoxyribonucleic acid, is the genetic material of most organisms, which is a major constituent of chromosomes within the cell nucleus and plays a major role in the determination of the hereditary characteristics by controlling protein synthesis in cells. [1]


History
In 1869, Swiss physician Friedrich Miescher noted a microscopic substance in the pus of discarded surgical bandages, which he called “nuclein”, because it was found to reside in the nucleus of the cells.

The term “gene” was coined in 1909 by Danish botanist Wilhelm Johannsen, invented to describe the “particles” of inheritance that pass characteristics from one generation to another.

The base, sugar, and phosphate nucleotide units to Miescher’s nuclein pus were identified in 1919 by Russian-American biochemist Phoebus Levene.

In 1937, English molecular biologist William Astbury produced X-ray diffraction patterns which showed a regular structure of the genetic substance.

In 1944, Austrian physicist Erwin Schrödinger published his famous "What is Life?" Dublin lecture, in which he outlined the physics, chemistry, and thermodynamics of what he called the "hereditary substance", described as a type of molecular aperoidic crystal chromosome fibre. [2]

Schrodinger's physical science model stimulated the direction of American James Watson, who in 1947 had plans to complete his PhD dissertation on the gene and Indiana University.

In 1953, biochemists James Watson and Francis Crick famously elucidated the three-dimensional structure for what they called the “salt of deoxyribose nucleic acid (D.N.A.) in their famous article “Molecular Structure of Nucleic Acids”. [5]

Vitalism
In the years to follow, religiously-inclined thinkers began to seize on premise of DNA being the essence or secret of life or key to the transmission of life by inserting hypothetical vitalism models into the picture.

“The ‘central dogma’ of molecular biology, which states that the information upon which the chemistry of life depends is provided by the genetic material DNA. But the refusal of biologists to regress further than this point and to confront the question as to where the information contained in DNA came from in the first place has, according to Stephen Black [1972], reintroduced a quasi-vitalism in to biology.”
Michael Foley (1990), Laws, Men and Machines [7]

This resulted in Crick writing a 1966 response book called Of Molecules and Men, in which he describes the position of several scientists who posit an invisible, purposeful substance or influence which cause life to exist within the gene, called vitalism. Crick is highly critical of this position as being based on wishful thinking, or an attempt to support a theological assumption. [6]

A resent type of vitalism-insertion model is the 2007 genopsych theory of Indian chemical engineer DMR Sekhar who argues that something called "geno-psych" exists inside of the DNA molecule, and is an extensive thermodynamics property called running counter to entropy, driving (or self-driving) the genes in or into a state of consciousness, causing them to evolve, thus giving free will and choice to humans.

Mate selection | MHC
In sexual selection studies, it is found that mates are most attracted to opposites who have the most dissimilar major histocompatibility complex (MHC), a large genomic region or gene family found in most vertebrates. MHC genes make molecules that enable the immune system to recognize invaders; generally, the more diverse the MHC genes of the parents, the stronger the immune system of the offspring.

In a 1995 experiment by Swiss biologist Claus Wedekind, a group of female college students smelled t-shirts that had been worn by male students for two nights, without deodorant, cologne or scented soaps. Overwhelmingly, the women preferred the odors of men with dissimilar MHCs to their own. [3] Their preference, however, was reversed if they were taking oral contraceptives. This famous experiment is known as the “sweaty T-Shirt study”. [4]

References
1. Daintith, John. (2005). Oxford Dictionary of Science. New York: Oxford University Press.
2. Schrodinger, Erwin. (1944). What is Life? Cambridge: Cambridge University Press.
3. Wedekind, C.; Seebeck, T., Bettens, F. and Paepke, A. J. (1995). "MHC-dependent mate preferences in humans". Proc Biol Sci. 260 (1359): 245-249.
4. DNA Matching and the Magic of Chemistry – ScientificMatch.com 5. (a) Sekhar, DMR. (2007). "On the Incompatibilities of the Second Law of Thermodynamics, Primary Instincts, Natural Selection, and the Properties of DNA." (8-pages). Submitted as article proposal to the Journal of Human Thermodynamics.
(b) Genopsych – DMR Sekhar talk page (Wikiversity).
(c) Sekhar, DMR. (2009). “Genpsy: Genopsych – the self programmability of genome”, Google Knol, January.
5. Watson, James and Crick, Francis (1953). "Molecular Structure of Nucleic Acid", Nature, 4356: 737, Apr. 25.
6. Crick, Francis. (1966). Of Molecules and Men (abs). University of Washington Press.
7. (a) Black, Stephen. (1972). The Nature of Living Things: an Essay in Theoretical Biology (Maxwell’s demon, pgs. 4-6; God and DNA, pgs. 11-12). Butterworth-Heinemann, 2013.
(b) Foley, Michael. (1990). Laws, Men and Machines: Modern American Government and the Appeal of Newtonian Mechanics (pg. 84). Routledge, 2014.

Further reading
● Watson, James. (2003). DNA: the Secret of Life. Alfred A. Knopf.

External links
DNA – Wikipedia.

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