RTB questions human chromosome 2

Sure, go ahead. Go listen to Aj Roberts. Should be very enlightening. Enjoy. Good night.

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Thank you kindly. I was hoping to do so. Itā€™s what we are about here. Peaceful Science, having discussions with people from differing views hoping to find commonality.

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Yep, the community here is one of the least like an echo chamber of all online communities Iā€™ve frequented. Letā€™s try to keep it that way. The results have been really promising so far: for example, Joshā€™s engagement with the latest version of ID espoused by Eric would be unimaginable most other contexts. Even if people still disagreed, thereā€™s more clarity in all aspects of the argument.

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2 posts were split to a new topic: Find Common Ground OR Call Out Woo Science?

I am by no means an expert on chromosomal fusions, but the definition of Robertsonian fusion seems to vary a bit in the literature, and human chromosome 2 is frequently said to be a Robertsonian fusion. Now, the fusion is not at the centromeres. The two separate ape chromosomes are acrocentric, but they do have short arms beyond the centromeres. The two centromeres (one degenerate) of human chromosome 2 are thus separated by a short distance, as the fusion is at the telomeres.

Now the question is whether the various fusions known to be polymorphic within populations are all what @AJRoberts refers to as true Robertsonian fusions, in which there is only one centromere. If they all are, she has a point. If at least one is not, i.e. closer in nature to the human chromosome 2, then those polymorphisms are relevant and refute Ranaā€™s point that such a fusion would prevent reproduction and would be strongly selected against. I donā€™t know the answer to this. Itā€™s going to require a search of the literature. I donā€™t even know if the answers are known; it seems that it might require sequencing of the regions to tell the difference. Iā€™ll have to get back to you on that.

I also donā€™t know what Ranaā€™s model is. I presume it involves separate creation of humans and apes. (Is that right?) If so, then we hardly need chromosome fusion scenarios to show that model wrong. Humans and chimps are close relatives, and thereā€™s no way out of that. Given that conclusion, there is no way to avoid the further conclusion that there has been a chromosomal fusion in the human lineage. At the very most, one could claim that the fixation of that fusion would require divine intervention.

I also have a question for Rana or his proxies: what does the artificial fusion of yeast chromosomes have to do with the issue, as Rana makes a big deal of it?

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@AJRoberts I want to emphasize that several people asked @Patrick to back down. This is not an echo chamber. You are and will be treated fairly here. Sometimes there will be mistakes and errors made. The goal is to settle it in dialogue.

@AJRoberts is absolutely right here. Rana has acknowledged places they had it wrong. A key example is Sapiens interbreeding with Neanderthals:

To their credit, they have changed their position based on evidence. Also, here, you can see another adjustment by @AJRoberts.

This was in response to a direct correction I made to a claim by Rana on @purposenation. I do disagree with many things in the RTB model. However, I also believe that there is a basic desire to get things right at RTB. To the extent that they will let me, it is my aim to help them in that goal. Iā€™m sure there will still be disagreements at the end of the day. Those disagreements, however, might not be so large.

This is not clear to me either.

Sometimes it seems that there is a focus on making a negative case against evolution, rather than a positive case for how their model could make sense. The latter is more constructive than the former.

Iā€™m well aware.

Do you think it was fair for me to accuse Dr. Rana of not being familiar enough with the literature to know that it doesnā€™t require ā€œmilleniaā€ to inactivate a centromere in a fused dicentric chromosome? Do you think it was fair for me to accuse Dr. Rana of not being familiar enough with the literature to know that telomere-telomere fusion are usually associated with loss of telomere sequences?

I didnā€™t actually quote anything, I merely cited the article because it listed several primary sources documenting no decrease in fertility. I could have cited the articles directly, but why bother when one link would suffice? The blog also quotes the articles to give lay or casual readers the gist of what theyā€™re about. I donā€™t think thereā€™s anything wrong with linking to the blog post. I didnā€™t suggest that ā€œquoting it should merit the response of a scientistā€, although I think itā€™s pretty arrogant to brush it off as ā€œbeneath Dr. Ranaā€. Respond to the argument. Itā€™s not as though Dave Wiskerā€™s blog post was inarticulate or abrasive.

As @John_Harshman correctly points out, the term ā€œRobertsonian translocationā€ is actually used a bit inconsistently in the primary literature, not that has anything to do with what I said.

Yes. Why are you telling me as though I donā€™t know this, even as you point out that my own source says it? Do you think I didnā€™t read the paper or something? If you look at my original post again, youā€™ll see that the very first thing I said on the subject was ā€œItā€™s true that fertility can be reducedā€¦ā€ Unfortunately, there will always be a bias towards finding clinical problems associated with translocations - often the only reason to carry out a cytogenetic analysis is when a patient comes in with clinical problems. If a large sample of clinically ā€œnormalā€ people were to have their karyotype determined for the sake of it, Iā€™m sure weā€™d find many more chromosomal abnormalities with no outward effects.

Iā€™m not claiming that there are never any reductions in reproductive rate, Iā€™m saying that there are at least isolated cases where there seem to be no reductions in humans. Combined with the more rigorous non-human animal data, the conclusion is pretty clear: a difference in chromosome number is not an iron-clad barrier to reproduction or to a given translocation/fusion spreading through a population.

I feel like Iā€™m having to repeat myself a lot here: I never claimed that dicentric fusions in human chromosomes are not associated with various problems. Iā€™m saying that those problems are not necessary consequences of a fusion, while Dr. Rana insists that they are.

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@AJRoberts you are free to make any comments you want. All my comments about RTB is as an institution and not attacks on the people themselves. Everyone here realize that you, Faz, Hugh and others are paid staff members of RTB that work for your Christian Right donors, so we know that you have signed a statement of Faith that you must adhere to. That does effect RTBā€™s credibility by the general secular population. Like DI, RTB takes the results of evolutionary science and does one of two things with the new results:

  1. RTB will bash and attack real science inquiry and results if it doesnā€™t align with their Christian RTB model .
  2. RTB will find the Christian God in the new results just like Deb Haarsma found the Christian God in the multiverse after Stephen Hawkings death.

In doing number 1, RTB usually gets the science wrong as in the case of Chromosome 2 fusion and anything to do with any human species (especially Neanderthals) in the genius Homo. What it means to be human (language, culture, tool making,) has been going on at least since Homo Erectus and RTB has yet to amend their special creation model to reflect this. Sometimes they get the science right (Hugh Ross in astronomy) this is when RTB invokes number 2.

Remember RTB staff members are paid to do this. They are playing to their donors which are predominately Evangelical Christians who are caught between AiG, ID, Biologos and the ever advancing secular world of evolutionary science.

I have no ill will to you, Faz, Hugh, Jeff, or Ken, I just want you to know and everyone here that RTB is just another pawn in the wider culture wars we find ourselves in. Possibly a reluctant pawn but nevertheless a pawn.