CCR5-Δ32 is a deletion mutation of a gene that has …

Comment on How much of the Human Genome is Functional? by Sean Pitman.

CCR5-Δ32 is a deletion mutation of a gene that has a specific impact on the function of T cells. The deleted portion of the CCR5 gene consists of thirty-two base pairs that correspond to the second extracellular loop of the CCR5 receptor; the mutated CCR5 receptor is non-functional and does not allow M-tropic HIV-1 virus entry, thus resulting in infection resistance – exactly how many forms of antibiotic resistance are achieved. There is no problem, statistically, achieving such a mutation – even in a human population.

The Milano mutation in the HDL lipoprotein is also based on a single point mutational change (Link). The likely source of this mutation was traced to one man, Giovanni Pomarelli, who lived in the village in the late 18th century and passed it on to his offspring (Link). It is characterized by the replacement of arginine by cysteine at position 173. Statistically, such small mutations are relatively likely to be achieved in a relatively short time in human populations.

As far as mutations preventing various bacterial and viral infections, we really don’t need these since the immune system functions just fine based on pre-programmed random mutations and function-based selection within a fairly small “sequence space” of antibody options.

Now, I do agree with you that the detrimental mutation rate is the real problem since it significantly dwarfs the beneficial mutation rate and drives the human gene pool as a whole in a downhill direction. However, one should not argue that there are no such things as truly beneficial mutations – even within the human gene pool. There are many such examples in various environments. It only hurts your main position to argue otherwise.

Sean Pitman Also Commented

How much of the Human Genome is Functional?
Good response.


How much of the Human Genome is Functional?
You do realize that I’m not a neo-Darwinist? The evolutionary mechanism of random genetic mutations and natural selection is limited to the lowest levels of functional complexity. It cannot produce any qualitatively novel system that requires more than 1000 specifically arranged amino acid residues this side of trillions upon trillions of years of time (Link). It’s a statistical problem due to the nature of sequence space at higher and higher levels of functional complexity…


How much of the Human Genome is Functional?
@dana:

Prions are interesting. However, prions don’t really self-replicate themselves starting with random amino acids. Usually the same amino-acid residue sequence is required to already exist in a pre-formed protein before this pre-existing protein can then acquire the 3D prion conformation. The prion simply refolds the pre-existing protein with the same or similar sequence into a new conformational shape.

This isn’t like a self-replicating organism where randomly arranged nucleic acid molecules are specifically sequenced by protein-based machinery based on a pre-existing DNA sequence template. In other words, the way prions works is not like replicating a complex mechanical machine from scratch – from a pile of fundamental building blocks.


Recent Comments by Sean Pitman

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Thank you Ariel. Hope you are doing well these days. Miss seeing you down at Loma Linda. Hope you had a Great Thanksgiving!


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Thank you Colin. Just trying to save lives any way I can. Not everything that the government does or leaders do is “evil” BTW…


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Only someone who knows the future can make such decisions without being a monster…


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Where did I “gloss over it”?


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I fail to see where you have convincingly supported your claim that the GC leadership contributed to the harm of anyone’s personal religious liberties? – given that the GC leadership does not and could not override personal religious liberties in this country, nor substantively change the outcome of those who lost their jobs over various vaccine mandates. That’s just not how it works here in this country. Religious liberties are personally derived. Again, they simply are not based on a corporate or church position, but rely solely upon individual convictions – regardless of what the church may or may not say or do.

Yet, you say, “Who cares if it is written into law”? You should care. Everyone should care. It’s a very important law in this country. The idea that the organized church could have changed vaccine mandates simply isn’t true – particularly given the nature of certain types of jobs dealing with the most vulnerable in society (such as health care workers for example).

Beyond this, the GC Leadership did, in fact, write in support of personal religious convictions on this topic – and there are GC lawyers who have and continue to write personal letters in support of personal religious convictions (even if these personal convictions are at odds with the position of the church on a given topic). Just because the GC leadership also supports the advances of modern medicine doesn’t mean that the GC leadership cannot support individual convictions at the same time. Both are possible. This is not an inconsistency.