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Genetic literacy project: Are humans genetically loaded for extinction?

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File:DNA simple.svg From Andrew Porterfield at the Genetic Literacy Project:

idea called “genetic load” was developed in the 1930s by famed biologist J.B.S. Haldane, referring to any genome that had increasing numbers of deleterious mutations. The more mutations in a population, the more likely that members of that population couldn’t survive, ultimately threatening the fitness of that population. With enough mutations, a group couldn’t adapt as well to environments, and members would die off. Thus, there’s a limit to natural selection. Now, for some evolutionary biologists, the concept of genetic load has resurfaced as a genuine concern. …

He doesn’t think it’s that big a concern.

One problem is that modern sequencing has produced much more data, and shown us so many more ways that genes can vary (and be manipulated), and we need to get a better idea of what we’re looking at. Phenotypes can be neutral, and a vast amount of evolution is because of drift (earlobes, nose shape, and slight variations in eye color). And many variations are not conserved. More.

At one time, the Big Extinction was supposed to be World War III. Now that the genome has been mapped and the Big One put on hold, ppular worry shifts to genetics.

See also: Sixth mass extinction, but no news on defining “species”?

The Big One, as we remember it:

The physical universe is loaded for extinction according to thermodynamics. That we have existence at all shows divine intervention. tribune7
as to this comment from the article: "Minnesota biologist PZ Myers doesn’t think it’s so bad." Given PZ's cavalier 'excuse making' for all the failures found within Darwinian evolution, that is similar to saying a bank robber 'doesn't think it is so bad' that he robs banks. Others would sharply disagree with his cavalier attitude towards robbing banks, and in PZs case, sharply disagree with his cavalier attitude towards robbing science!
Using Computer Simulation to Understand Mutation Accumulation Dynamics and Genetic Load John Sanford1, John Baumgardner2, Wes Brewer3, Paul Gibson4, and Walter ReMine5 Abstract. Long-standing theoretical concerns about mutation accumulation within the human population can now be addressed with numerical simulation. We apply a biologically realistic forward-time population genetics program to study human mutation accumulation under a wide-range of circumstances. Using realistic estimates for the relevant biological parameters, we investigate the rate of mutation accumulation, the distribution of the fitness effects of the accumulating mutations, and the overall effect on mean genotypic fitness. Our numerical simulations consistently show that deleterious mutations accumulate linearly across a large portion of the relevant parameter space. This appears to be primarily due to the predominance of nearly-neutral mutations. The problem of mutation accumulation becomes severe when mutation rates are high. Numerical simulations strongly support earlier theoretical and mathematical studies indicating that human mutation accumulation is a serious concern. Our simulations indicate that reduction of mutation rate is the most effective means for addressing this problem. http://bioinformatics.cau.edu.cn/lecture/chinaproof.pdf Genetic Entropy - LATEST DEVELOPMENTS http://www.geneticentropy.org/latest-development

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