Denis Alexander, a prominent molecular biologist, believes that there is.
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The evangelist, who died Wednesday, believed science and religion were complementary.
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75% of the Human Genome Is Junk DNA, Claims New Research
New research by Professor Dan Graur shows that only a quarter of the human genome is functional.
30 July, 2017
DNA
<p class="p1">How much of the human genome, our genetic blueprint, actually makes us who we are? New work by an evolutionary biologist at the University of Houston suggests that only<strong> up to 25%</strong> of the human genome is functional. The other 75% are so-called “junk DNA” - useless sequences that don’t play a role in the important chemical reactions inside us. This conclusion goes sharply against the estimate of <strong>80%</strong> functionality proposed by the <a href="https://www.encodeproject.org/" target="_blank">ENCODE project,</a> an international public research consortium that has led the way in human genome exploration.</p> <p class="p1"><a href="http://nsmn1.uh.edu/dgraur/" target="_blank">Dan Graur,</a> professor of biology and biochemistry, calculated that about <strong>10 to 15 percent</strong> of the genome is actually functional, with the upper limit of 25 percent.<span> </span></p> <p class="p1">His reasoning stems from looking at how mutations affect a population’s DNA. Graur’s mathematical model allowed him to calculate the <strong>“mutational load” </strong>- the total genetic load of a population that results from the accumulation of bad or <strong>deleterious</strong> mutations. At some point the load can become too much and the population would go extinct.<span> </span> </p> <p class="p1">Graur’s work related how reproductive success, the ability of a species to replenish itself, was decreased by the deleterious mutations. Over time, humans would have to reproduce at an impossible high rate to keep up with the mutations, Graur concluded.</p> <p class="p1">The professor explained why he finds the 80% functionality of the genome <a href="https://ghr.nlm.nih.gov/primer/genomicresearch/encode" target="_blank">proposed by the ENCODE scientists</a> as unrealistic:</p> <blockquote>
<p class="p3"><span class="s1">“For 80 percent of the human genome to be functional, each couple in the world would have to beget on average <strong>15 children</strong> and all but two would have to die or fail to reproduce,” <a href="http://www.uh.edu/news-events/stories/2017/JULY%2017/07142017Graur-functional-genome.php" target="_blank">writes Graur.</a> “If we use the upper bound for the deleterious mutation rate (2 × 10</span><span class="s2">−8</span><span class="s1"> mutations per nucleotide per generation), then … the number of children that each couple would have to have to maintain a constant population size would exceed the number of stars in the visible universe by ten orders of magnitude.”</span></p>
</blockquote> <p class="p5">This is not the first time Graur fought against the 80% claim. In a <a href="https://evolutionnews.org/2014/04/dan_graur_the_v/" target="_blank">2014 interview</a> with <em>Science</em> magazine, Graur even claimed its proponents are essentially pitching the idea of “intelligent design”. To Graur, asserting 80% usability implies that most of the genome exists to serve a purpose. Instead, he believes that “<span class="s3">everything is shaped by evolution,” a slow process that weeds out useless features through genetic mutations - the drivers of evolution. This process also accumulates a lot of junk in the human genome.</span></p> <p class="p5">Why is it important to know that only a quarter of the human genome may have functionality? Graur believes his work can shift the focus in the field of human genomics to what is useful from a medical standpoint: </p> <blockquote>
<p class="p3"><span class="s1">“We need to know the functional fraction of the human genome in order to focus biomedical research on the parts that can be used to prevent and cure disease,” <a href="http://www.uh.edu/news-events/stories/2017/JULY%2017/07142017Graur-functional-genome.php" target="_blank">said Graur</a>. “There is no need to sequence everything under the sun. We need only to sequence the sections we know are functional.”</span> </p>
</blockquote> <p class="p5">You can read the study <a href="https://academic.oup.com/gbe/article/3952726/An-upper-limit-on-the-functional-fraction-of-the?searchresult=1" target="_blank">here</a> in Genome Biology and Evolution.<span> </span></p>
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On the Origins of Genius: How Human Consciousness Evolved
The human mind is like a Turing machine, says Daniel Dennett. It's made up of unthinking cogs – but when combined in the right order, their motion gives rise to consciousness.
10 February, 2017
Daniel Dennett has been mulling consciousness over for the last 50 years, and he’s ended up where we began: evolution. When this theory was proposed by Darwin, it inverted everything people at the time held to be true – it revealed that we were not created by intelligent design, but rather we evolved into intelligent designers ourselves. The process of evolution worked mindlessly, producing better and better human prototypes, crafting ever-more complex brains until that rhythmic, algorithmic, repetition birthed consciousness. This is what Dennett refers to as ‘competence without comprehension’. Daniel Dennett's most recent book is From Bacteria to Bach and Back: The Evolution of Minds.
<p>Daniel Dennett's most recent book is <a href="http://www.indiebound.org/book/9780393242072"><i>From Bacteria to Bach and Back: The Evolution of Minds</i></a>.</p><p><a href="http://www.indiebound.org/book/9780393242072"><img height="150" src="%5Cr%5Cnhttps://s3.amazonaws.com/edge-misc-assets/Book+Covers/Daniel+Dennett.jpg" width="225"></a></p>
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