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To: ifinnegan
I don’t think he left it out, that’s the point. It’s easy to compare cDNA for genes. Not so easy to compare genome structures of 23 and 24 chromosomes in context of all the DNA.

No, it was a purposeful omission, meant to deceive those who do not have a solid background in the life sciences. Unfortunately, that is behavior that seems characteristic of those who actually have the knowledge base to speak of such matters, but decide to misuse that knowledge for personal profit.

The genome project and comparative functional genomics have shown that the key to differences in species is in the non-coding sequences and how the corresponding chromosomal structures regulate development and morphology by spatial-temporal regulation is, to my mind, the biggest question in biology.

Again, you need to understand the complete picture.

*Most* non-coding regions are filler. For instance, the introns contained in most chromosomal genes, which have no functional purpose other than to add size to a gene (and facilitate evolutionary mechanisms). As long as the sequences at the ends of the introns remains conserved, the rest can be any sequence at all without changing the function. Since there is no selective pressure to keep those sequences from mutating, they mutate the most rapidly. If you want to find out when humans and chimps started to diverge from a common ancestor, you would look at the number of mutations in those sequences, which roughly corresponds to the length of time since the two populations diverged.

Some non-coding DNA affects the expression levels of genes. Let's say that full expression of a gene leads to a cell containing 5% of a specific protein. But the cell does not want to consist of 5% of that protein, so the regulatory elements of DNA decrease the level of expression to the level that the cell needs, which could be 0.1% or zero except when the cell senses changes in its environment. The regulatory elements are interesting in that studying them gives insights into development and so forth. But if you are considering the actual genetic difference between two species, they also do not give a clear picture. A single change in a regulatory element can have a disproportionately large effect on function--which means that you could compare those between humans and chimps and find less than 1% difference. An example of how modulation in regulation affects function is skin color: all humans have the same mechanism for producing melanin, yet we range in color from ivory white to ebony black. That is because we regulate expression at different levels.

So I focus on the coding regions as the most pertinent when it comes to comparing the DNA level differences between two species. That is because the coding regions translate to proteins, and the functional molecules of organisms are proteins. Proteins direct how your bones are shaped, how your muscles are formed, the shape of your organs, etc. etc. Because of redundancy in the codon code, the DNA that codes for proteins can change slightly without changing the protein. So I compare the differences between coding regions and between proteins to come up with a more complete picture.

There is much, much, more to consider when comparing the similarity of two organisms--I spent seven years working on my biochemistry and molecular biology Ph.D., focusing on the structure and function of a single protein and trying to understand why, even though this protein functions identically in species as diverse as fish and humans, there are some very distinct differences in the effects of that function once the protein is (lethally) activated. But rather than getting into a dissertation length discussion of all of the intricacies of DNA structure and the implications on higher-order functions, I'll just point out that these complexities are completely consistent with evolutionary theory. Furthermore, it is because of the context provided by evolutionary theory that I am able to make predictions about what to look for if, for example, I want to find the protein responsible for a particular function in a species that has not been previously characterized with respect to that function. The 98-99% similarity between chimp and human genomes really is not significant when it comes to understanding the implications of how and when the two species diverged--it's basically just a fun trivia fact.

116 posted on 06/03/2017 6:30:51 AM PDT by exDemMom (Current visual of the hole the US continues to dig itself into: http://www.usdebtclock.org/)
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To: exDemMom

and just for the record- that ‘non science site’ as you put it puts thel ie to several major chimp human studies throughout history- but we’ll just gloss right over that fact simply because it’s a ‘Christian site’ and by golly Christian sites ‘can’t possibly have anything truthful or worht reading it them’- bias much?


118 posted on 06/03/2017 8:51:59 AM PDT by Bob434
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To: exDemMom

had you bothered to read the ‘Christian site’ you would have seen that several of the papers did not focus simply on the non coding areas or the ‘redundant’ areas, and that they actually went into great detail discussing how dissimilar the coding regions that were thrown out because they didn’t fit the agenda really were-

Pots shouldn’t call kettles black- you speak of ‘real science’ yet show a distinct unwillingness to engage in honest discussions when it comes to evidences that call into question your preferred belief- dismissing with a wave of the hand any such evidences, and attacking the messenger- all things that ‘real scientists’ don’t engage in- a ‘real scientists woudl take the facts, in this case, the claims made by such websites as i listed, and refute the points instead of attacking the author- if your position is strong enough your evidences should be strong enough to withstand such challenges- but when you accuse the author of things like ‘cherry picking’ and ‘deceit’ when your side does the very same thing- it simply shows a lack of strength on your own arguments-

[[*Most* non-coding regions are filler.]]

*MOST* as in? As in some are not simply filler? Again- the question is put to you- how much of the ‘filler’ is being included, and is there the chance that species specific filler might be important to that particular kind?

I’m willing to have a discussion based on your comments and the facts you present, and not your character- it would be nice if you could return the favor without resorting ot the tired out mantra of Christian bashing- I pointed you to that site because it challenges the things you were claiming- waving the site away simply because it is a ‘Christian site’ and implying that nothing o n the site could possibly be of any scientific value because it’s all ‘not real science’ isn’t very scientific of you-

[[Let’s say that full expression of a gene leads to a cell containing 5% of a specific protein. But the cell does not want to consist of 5% of that protein, so the regulatory elements of DNA decrease the level of expression to the level that the cell needs, which could be 0.1% or zero except when the cell senses changes in its environment.]]

Are you describing bacteria utilizing ‘nylon digestion capabilities’ shoudl the environment ‘change’? Would that be such a case?


120 posted on 06/03/2017 9:08:15 AM PDT by Bob434
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To: exDemMom

“*Most* non-coding regions are filler.”

You’re 20 years behind the times at least.

Are you no longer in the field?

Did you not read my post?

Thanks for your response, but i didn’t expect obsolete boilerplate.

“As long as the sequences at the ends of the introns remains conserved, the rest can be any sequence at all without changing the function.”

DNA is an amazing molecule (as is RNA) you should look in to it some day.

Too many people, yourself apparently included, think nucleic acids are generic blocks with a static structure.


132 posted on 06/03/2017 12:42:03 PM PDT by ifinnegan (Democrats kill babies and harvest their organs to sell)
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To: exDemMom

What makes a mouse as opposed to a chimp or rat?


133 posted on 06/03/2017 12:44:44 PM PDT by ifinnegan (Democrats kill babies and harvest their organs to sell)
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To: exDemMom

Here’s a good article to read. (Chromatin structure and function is where it’s at).

A comparative encyclopedia of DNA elements in the mouse genome

The laboratory mouse shares the majority of its protein-coding genes with humans, making it the premier model organism in biomedical research, yet the two mammals differ in significant ways. To gain greater insights into both shared and species-specific transcriptional and cellular regulatory programs in the mouse, the Mouse ENCODE Consortium has mapped transcription, DNase I hypersensitivity, transcription factor binding, chromatin modifications and replication domains throughout the mouse genome in diverse cell and tissue types. By comparing with the human genome, we not only confirm substantial conservation in the newly annotated potential functional sequences, but also find a large degree of divergence of sequences involved in transcriptional regulation, chromatin state and higher order chromatin organization. Our results illuminate the wide range of evolutionary forces acting on genes and their regulatory regions, and provide a general resource for research into mammalian biology and mechanisms of human diseases.

http://www.nature.com/nature/journal/v515/n7527/full/nature13992.html


136 posted on 06/03/2017 12:57:59 PM PDT by ifinnegan (Democrats kill babies and harvest their organs to sell)
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To: exDemMom

“I spent seven years working on my biochemistry and molecular biology Ph.D.”

Took me five.

25 years on now.


174 posted on 06/04/2017 12:50:41 AM PDT by ifinnegan (Democrats kill babies and harvest their organs to sell)
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