Nope.
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Loss of genetic complement is often bad, especially when it is a lot at once. Aneuploidy, including the partial aneuploidies that happen with many rearrangements, is also usually bad even though you still have all the genes because you have the wrong number of copies. But an individual with the right number of the right genes will often be fine regardless of how those genes are arranged, save for having difficulty reproducing (since offspring will tend to have some form of aneuploidy). How much difficulty depends on the specifics of the rearrangement.
It has happened in humans several times.
Can you provide a concrete definition of ‘kinds’?
There are interstitial telomeric sequences, which look like telomeres (in that they are composed of the standard repeat) but aren’t telomeres (that is, they don’t complex with the relevant proteins to form the actual telomere structure). Many of these, like the one in Hsa2, line up with apparent recombinations, so may be the remnants of telomeres. To my knowledge, there are no examples of head-to-head repeats (like those found in the Hsa2 fusion site) not associated with recombination sites.
Mammalian centromeres are characterized, at least in part, by large amounts of alphoid repeats and some other heterochromatin. Alphoid repeats are found elsewhere, but extremely rarely. @evograd made a figure (below) showing the blocks of these repeats, with only two large blocks not at the centromere itself. One was on Hsa9 and the other on Hsa2.
So the answer to your question is: Very rarely, but never with this degree of correspondence when not associated with an apparent rearrangement.
You did it again.
chromosomal fusion sites of living animals in nature, not telomere-telomere fusions
This is Tomkins being intentionally obtuse. SatDNA is commonly found in subtelomeric regions, and it is the subtelomeric regions that actually fuse, not the telomeres proper. There are examples of subtelomeric fusions, mostly involving the the satDNA of subtelomeric regions. and degenerate repeats. While the specific nature of the Hsa2 fusion is fairly unlikely, it is also even more obviously the result of a fusion! It is like saying that someone could not possibly have won a hand of poker because they got a royal flush, arguing that since it is such a rare hand it must be a bad one.
Also, I believe that there are documented telomere-telomere fusions in pigs and zebras. So…
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Has Todd or anyone provided a rebuttal to Tompkins argument? @CrisprCAS9 @thoughtful have you read this?
Chromosome fusion Thompkins.pdf (589.7 KB)
Horizontal gene transfer of transposons is fairly common. That said, any claim of horizontal gene transfer from a new genome assembly should be treated with some caution, as there is always a strong possibility of DNA contamination from other species winding up in a new, minimally curated assembly. There have been some high profile claims of widespread HGT from new genome assemblies that turned out to be from contamination.
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Yes, I’ve read that. Dozens of people, myself included, have explained why his argument is meritless. In fact, so many people have ripped apart the linked blog post from Tomkins (and please note the spelling, for his sake!) so completely that I wonder if you have ever looked for a rebuttal.
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I would appreciate it if you would cite the one you think has the most credibility. I appreciate the papers you cited supporting a fixation model. They appear to require strong positive selection. Do you disagree?
Sure, but first can you cite the one that you’ve seen that you think has the most credibility? Because you’ve looked, right? And I’d hate to link one you’ve already read.
Generally, yes. Alternatively, there is naturally a homozygote advantage, so the heterozygote could spread by drift in a large population, and become fixed following a bottleneck.
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Here is what I read in the last 6 months. It was authored by @cwhenderson on Bio Logos
I’d recommend checking Roohif’s (in your link) other posts on the subject, along with those by our own EvoGrad on his site, and those by Larry Moran at https://sandwalk.blogspot.com/. Also, I’d suggest taking a look at this presentation on the subject by Jackson Wheat, along with his extensive list of sources in the description.
If you’d link, I can reproduce my previous commentary on the subject into a single post for a new thread, although that would take a bit of time. Most of it was ‘lost’ when G+ was shut down. I’ve got an archive of everything, but it would require extensive reformatting. On the other hand, that is something I’ve been meaning to do, anyway.
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Yes I agree that @roohif ’s article is where to start.
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From Wikipedia:
Robertsonian translocation ( ROB ) is a chromosomal abnormality wherein a certain type of a chromosome becomes attached to another. It is the most common form of chromosomal translocation in humans, affecting 1 out of every 1,000 babies born. It does not usually cause health difficulties, but can in some cases result in genetic disorders such as Down syndrome and Patau syndrome.[1] Robertsonian translocations result in a reduction in the number of chromosomes…
In humans, Robertsonian translocations occur in the five acrocentric chromosome pairs (chromosome pairs where the short arms are fairly short), namely 13, 14, 15, 21 and 22. The participating chromosomes break at their centromeres and the long arms fuse to form a single, large chromosome with a single centromere.
1 in 1000 is not at all uncommon.
Chromosomes 2a and 2b in the chimp, the ones that fused in our lineage, are acrocentric.
Do you need more, or does that point you in the right direction?
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I’m starting to watch the video…but I’ve been laughing here for at least a full minute. I’m almost crying. Hearing the host say “email him and tell him how s*** his research is” in an Australian accent was hilarious for some reason.
blaming autocorrect on my phone.
Better yet, I’m blaming both of these things on pregnancy. Best excuse ever. Ok, now back to trying to understand things.
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I checked the two papers the YouTuber gave as evidence and as far as I could tell they were not describing extant animals, so technically Tomkins may be correct in those sentences…BUT for creationists the papers would describe animals in the same kind, so that’s the big question to ask him because it seems misleading then.
Thanks @CrisprCAS9 @evograd @Faizal_Ali for the information. Still trying to digest the words and what they mean. Real question: did you have to spend a lot of time memorizing terms in undergrad or grad or did you learn them along with practical knowledge so it wasn’t that hard?
Just reading descriptions like these without context of a story or video or visual and just looking up definitions, doesn’t make genetic or biological terms sink in for me really quickly. I’m hoping I’m not just a dunderhead and this isn’t a typical way to learn quickly.
@Faizal_Ali I assume for you it is a hobby or did you have to cover any of this in your education?
It’s not that difficult really. You expect something on hypothesis A you don’t on B. You find it, it supports A. You will not find an excuse not to understand this by chasing everything ever written about chromosomal alterations.
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I don’t know if you had already mentioned this but, if so, I missed it.
Congratulations!!
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Genetics is an important part of a medical education, and very pertinent to modern biological psychiatry. One of my teachers was a pioneer in the genetics of psychosis.
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Pigs and zebras aren’t extant animals?
Yes.
Okay, serious answer: There are a lot of terms you need to learn, but learning them in context can help because it fixes the meaning to that context. It also helps to learn a bit of Greek and Latin, so that you can work out the meaning from root words (‘telo’=end, ‘mere’=part, so ‘telomere’=end-part). But sometimes you just have to plow through until it sticks.
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Sure, but I’m just trying to understand the terms used to describe the process of chromosomal alterations.
Thanks. I thought I had groused so much about morning sickness in my posts, that no one had missed it. (Ii like to feel sorry for myself) 
Still lingering; don’t know what the little bugger is doing in there to need so many nausea-causing hormones; now he or she is making some obvious movements sticking her head into my side. Already acting like he/she owns the place. 
Thanks! I had forgotten about that aspect - very important.
The pig paper was referring to a common ancestor. I’m not sure about the zebra paper because I couldn’t get farther than the abstract, so I’m giving him the benefit of the doubt that it’s referring to a past event.
Thanks! I feel like I’ve learned a lot in the past 6 months. A very interesting field - I can see why you choose it.
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Yeah, the common ancestor… of pigs. I thought that was what you wanted? Babirusas and pigs can hybridize, so I can’t imagine what the problem would be. And in the context of what Tomkins has claimed, I don’t know what else could be asked for.
We usually don’t write papers about future events. As they haven’t happened yet, it is difficult to get the data.
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You should be aware of how you look in your comments here. You seem to bend over backwards finding excuses that let you doubt what scientists tell you, while bending over backwards (the other backwards?) finding excuses that let you believe what creationists tell you. Stop relying on excuses; that would be better.
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