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At PLOS: “Genes – way weirder than you thought”


File:DNA simple.svg From Mike Klymkowsky at PLOS:

Through his studies on peas, Gregor Mendel was the first to clearly identify some of the rules for the behavior of these inheritable factors using highly stereotyped, and essentially discontinuous traits – a pea was either yellow or green, wrinkled or smooth. Such traits, while they exist in other organisms, are in fact rare – an example of how the scientific exploration of exceptional situations can help understand general processes, but the downside is the promulgation of the idea that genes and traits are somehow discontinuous – that a trait is yes/no, displayed by an organism or not – in contrast to the realities that the link between the two is complex, a reality rarely directly addressed (apparently) in most introductory genetics courses. Understanding such processes is critical to appreciating the fact that genetics is often not destiny, but rather alterations in probabilities (see Cooper et al., 2013). Without such an more nuanced and realistic understanding, it can be difficult to make sense of genetic information. More.

Can’t speak for others but here at Uncommon Descent, we have been thinking that for quite some time. We’re not shocked but we are annoyed when discredited textbook Darwinism is treated as the norm and the true state of affairs is treated as a big surprise.

See also: Bale monkeys more closely related to sister species than same species in different locationsThe “biological species concept” is yet another textbook dead zone.

Girl got mostly a double set of her dad’s genes, is almost a twin. She has some problems but she is 11 years old. Yes, that was the sound of another lectern splintering in the near distance.

Almost one in five genes’ coding status is unresolved Researchers: We believe that the three reference databases currently overestimate the number of human coding genes by at least 2000, complicating and adding noise to large-scale biomedical experiments.

Do all genes affect every complex trait? Veronique Greenwood: The roots of many traits, from how tall you are to your susceptibility to schizophrenia, are far more tangled. In fact, they may be so complex that almost the entire genome may be involved in some way

It is not your grandfathers gene anymore. A few notes to that effect:
Why the 'Gene' Concept Holds Back Evolutionary Thinking - James Shapiro - 11/30/2012 Excerpt: The Century of the Gene. In a 1948 Scientific American article, soon-to-be Nobel Laureate George Beadle wrote: "genes are the basic units of all living things.",,, This notion of the genome as a collection of discrete gene units prevailed when the neo-Darwinian "Modern Synthesis" emerged in the pre-DNA 1940s. Some prominent theorists even proposed that evolution could be defined simply as a change over time in the frequencies of different gene forms in a population.,,, The basic issue is that molecular genetics has made it impossible to provide a consistent, or even useful, definition of the term "gene." In March 2009, I attended a workshop at the Santa Fe Institute entitled "Complexity of the Gene Concept." Although we had a lot of smart people around the table, we failed as a group to agree on a clear meaning for the term. The modern concept of the genome has no basic units. It has literally become "systems all the way down." There are piecemeal coding sequences, expression signals, splicing signals, regulatory signals, epigenetic formatting signals, and many other "DNA elements" (to use the neutral ENCODE terminology) that participate in the multiple functions involved in genome expression, replication, transmission, repair and evolution.,,, Conventional thinkers may claim that molecular data only add details to a well-established evolutionary paradigm. But the diehard defenders of orthodoxy in evolutionary biology are grievously mistaken in their stubbornness. DNA and molecular genetics have brought us to a fundamentally new conceptual understanding of genomes, how they are organized and how they function. http://www.huffingtonpost.com/james-a-shapiro/why-the-gene-concept-hold_b_2207245.html Duality in the human genome - Nov. 28, 2014 Excerpt: The results show that most genes can occur in many different forms within a population: On average, about 250 different forms of each gene exist. The researchers found around four million different gene forms just in the 400 or so genomes they analysed. This figure is certain to increase as more human genomes are examined. More than 85 percent of all genes have no predominant form which occurs in more than half of all individuals. This enormous diversity means that over half of all genes in an individual, around 9,000 of 17,500, occur uniquely in that one person - and are therefore individual in the truest sense of the word. The gene, as we imagined it, exists only in exceptional cases. "We need to fundamentally rethink the view of genes that every schoolchild has learned since Gregor Mendel's time.,,, According to the researchers, mutations of genes are not randomly distributed between the parental chromosomes. They found that 60 percent of mutations affect the same chromosome set and 40 percent both sets. Scientists refer to these as cis and trans mutations, respectively. Evidently, an organism must have more cis mutations, where the second gene form remains intact. "It's amazing how precisely the 60:40 ratio is maintained. It occurs in the genome of every individual – almost like a magic formula," says Hoehe. http://medicalxpress.com/news/2014-11-duality-human-genome.html Gene Pleiotropy Roadblocks Evolution by Jeffrey P. Tomkins, Ph.D. - Dec. 8, 2016 Excerpt: Before the advent of modern molecular biology, scientists defined a gene as a single unit of inheritance. If a gene was found to influence multiple externally visible traits, it was said to be pleiotropic—a term ?rst used in 1910.2 During this early period of genetic discovery, pleiotropy was considered to be quite rare because scientists assumed most genes only possessed a single function—a simplistic idea that remained popular throughout most of the 20th century. However, as our understanding of genetics grew through DNA science, it became clear that genes operate in complex interconnected networks. Furthermore, individual genes produce multiple variants of end products with different effects through a variety of intricate mechanisms.2,3 Taken together, these discoveries show that pleiotropy is a common feature of nearly every gene.,,, The pleiotropy evolution problem is widely known among secular geneticists, but rarely discussed in the popular media. In this new research report, the authors state, "Many studies have provided evidence for the ability of pleiotropy to constrain gene evolution.",,, "Our study provided supportive evidence that pleiotropy constraints the evolution of transcription factors (Tfs).",,, The authors state, "We showed that highly pleiotropic genes are more likely to be associated with a disease phenotype.",,, http://www.icr.org/article/9747 The next evolutionary synthesis: from Lamarck and Darwin to genomic variation and systems biology – Bard - 2011 Excerpt: If more than about three genes (nature unspecified) underpin a phenotype, the mathematics of population genetics, while qualitatively analyzable, requires too many unknown parameters to make quantitatively testable predictions [6]. The inadequacy of this approach is demonstrated by illustrations of the molecular pathways that generates traits [7]: the network underpinning something as simple as growth may have forty or fifty participating proteins whose production involves perhaps twice as many DNA sequences, if one includes enhancers, splice variants etc. Theoretical genetics simply cannot handle this level of complexity, let alone analyse the effects of mutation.. http://www.biosignaling.com/content/pdf/1478-811X-9-30.pdf Gene previously linked to obesity is unrelated - June 29, 2015 Excerpt: … in the real world of careful analysis, scientists are just not finding the “genes” that the headline writers need. British geneticist Steve Jones points out that most human traits are influenced by so many genes that there is no likely systematic cause and effect: "We know of more than 50 different genes associated with height … That has not percolated into the public mind, as the Google search for “scientists find the gene for” shows. The three letter word for — the gene FOR something — is the most dangerous word in genetics." And the craze is not harmless, he warns. … https://uncommondesc.wpengine.com/genetics/gene-previously-linked-to-obesity-is-unrelated/ What If (Almost) Every Gene Affects (Almost) Everything? - JUN 16, 2017 Excerpt: If you told a modern geneticist that a complex trait—whether a physical characteristic like height or weight, or the risk of a disease like cancer or schizophrenia—was the work of just 15 genes, they’d probably laugh. It’s now thought that such traits are the work of thousands of genetic variants, working in concert. The vast majority of them have only tiny effects, but together, they can dramatically shape our bodies and our health. They’re weak individually, but powerful en masse. https://www.theatlantic.com/science/archive/2017/06/its-like-all-connected-man/530532/ Theory Suggests That All Genes Affect Every Complex Trait - June 20, 2018 Excerpt: Mutations of a single gene are behind sickle cell anemia, for instance, and mutations in another are behind cystic fibrosis. But unfortunately for those who like things simple, these conditions are the exceptions. The roots of many traits, from how tall you are to your susceptibility to schizophrenia, are far more tangled. In fact, they may be so complex that almost the entire genome may be involved in some way,,, One very early genetic mapping study in 1999 suggested that “a large number of loci (perhaps > than 15)” might contribute to autism risk, recalled Jonathan Pritchard, now a geneticist at Stanford University. “That’s a lot!” he remembered thinking when the paper came out. Over the years, however, what scientists might consider “a lot” in this context has quietly inflated. Last June, Pritchard and his Stanford colleagues Evan Boyle and Yang Li (now at the University of Chicago) published a paper about this in Cell that immediately sparked controversy, although it also had many people nodding in cautious agreement. The authors described what they called the “omnigenic” model of complex traits. Drawing on GWAS analyses of three diseases, they concluded that in the cell types that are relevant to a disease, it appears that not 15, not 100, but essentially all genes contribute to the condition. The authors suggested that for some traits, “multiple” loci could mean more than 100,000. https://www.quantamagazine.org/omnigenic-model-suggests-that-all-genes-affect-every-complex-trait-20180620/ Genes and Organisms: Improvising the Dance of Life - Stephen L. Talbott - Nov. 10, 2015 Excerpt: The performances of countless cells in your body are redirected and coordinated as part of a global narrative for which no localized controller exists.,,, A decisive problem for the classical view of DNA is that “as cells differentiate and respond to stimuli in the human body, over one million different proteins are likely to be produced from less than 25,000 genes”.30 Functionally, in other words, you might say that we have over a million genes.,,, http://www.natureinstitute.org/txt/st/org/comm/ar/2015/genes_29.htm
At the 10:30 minute mark of the following video, Dr. Trifonov states that the concept of the selfish gene 'inflicted an immense damage to biological sciences', for over 30 years:
Second, third, fourth… genetic codes - One spectacular case of code crowding - Edward N. Trifonov - video https://www.youtube.com/watch?v=fDB3fMCfk0E
The “biological species concept” is yet another textbook dead zone. I have no trouble with the earlier concept that any mating pair producing viable offspring are of the same species. As far as I am concerned that is a sensible dividing line and was only abandoned for political reasons. One of the signs of a failed idea is the need to keep changing definitions. ScuzzaMan
>Was it luck that Gregor Mendel did his experiments on something that had such distinct traits; Perhaps he selected a plant (in general, for its ease of propagation) which had characteristics that appeared to come in the fewest number of discrete variations. (And then he selected those particular characteristics.) Sort of like how the first physical laws we were able to formalize were the simplest to discover (linear relationships first, etc.) EDTA
Was it luck that Gregor Mendel did his experiments on something that had such distinct traits; otherwise he might never have arrived at his theories of hereditary. aarceng

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