Would love to hear the local experts' take on Philip Ball's How Life Works: A User's Guide to the New Biology

Still having not watched the video, here are my reactions to what you describe. It’s a bit lengthy, so don’t feel bad if you scroll past it. I thought people might want to hear reactions from someone who works in biology.

We are leaps and bounds past where we were in the 60’s and 70’s with respect to understanding life’s inner workings. I wouldn’t describe our understanding as limited. Rather, we now know so much it is hard to integrate all of it together.

Biologists still believe that DNA is a major aspect of understanding how life works.

Some genes are quite large, but that is just a nitpick. The Human Genome Project was an initial draft, as it says in the very title of their 2001 paper. The main goal of the project was to find the order of bases in the genome for as much of the genome as was practical at the time. When they published in 2001 there were still some gaps to fill, but they got over 90% of the genome sequenced (if memory serves). They were also able to propose some sort of function or history for a lot of the genome (e.g. genes, transposons), and that has only been added to in the last 20+ years.

For me, the story of technology and how it interacted with the HGP is as fascinating as anything else. It was very much like the emergence of transistors and computers earlier in history. The ability to sequence DNA improved massively during the project due to huge technological breakthroughs, as did the ability to understand the sequence itself.

The Central Dogma is often misunderstood. When Crick invented the Central Dogma he didn’t know how proteins were made from DNA/RNA. In fact, the point of the Central Dogma was to point to the best avenues for figuring that out. The Central Dogma states that sequence information can be passed between the nucleotides and from nucleotides to proteins, but sequence information can not be passed from proteins to nucleotides. IOW, once sequence information is moved into proteins it can’t get back out.

The other big piece of knowledge was that the sequence of amino acids in a protein were somehow copied from the order of bases in DNA.

I’m not sure what the current estimate is on non-coding functional transcripts compared to coding transcripts. What I will say is that about 10% of the human genome is functional, and 2% of that is coding DNA. Therefore, there is about 4 times as much functional non-coding DNA as there is coding DNA.

Descriptions like “a higher level” usually aren’t that helpful in science, a minor nitpick. One of the discussions going on right now in biology is what percentage of differently spliced transcripts are functional or just errors in splicing. I think there is a big question as to how many of the differently spliced transcripts are even translated into proteins.

It’s that cross talk that makes biology so complex and difficult to predict.

One thing that still intrigues me is identical twins. They have the same genome, and sure enough they develop exactly the same (within reason). They are the same in so many different physical attributes, so much so that strangers can not tell them apart in many cases. So why is this? Obviously, DNA has a very strong role to play here. How much is up for debate, but there is no denying the influence.

One way I think of this is that embryonic development is not nearly as rigid and brittle as computer programs. If I leave out a quote mark or parentheses somewhere in my Python script is stops working, but development seems to absorb the bumps along the way.

Again, I go back to identical twins. Why do they look so much alike? Also, it’s not as if dogs are giving birth to turtles, bats, and fish. Obviously, the plan is in the genome.

If by “higher level” he means interaction between genes and between genes and the environment, then yes.

No one chooses to be a hemophiliac. At the same time, there is an interplay between genetic destiny and freedom of choice.

It is worth noting that the humble Caenorhabditis elegans is a fascinating model used in the lab. The adult is made up of ~1000 cells, and it has a similar gene count to that of humans. Scientists were able to track gene expression in all cells from a single celled zygote to a full adult. This includes the development of neuronal cells.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3032935/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6581053/

Science has a tough time dealing with subjective terms like “aliveness”. Science is looking for something to measure. However, scientists are human like anyone else, so they absolutely do ponder these subjective, emotive, and philosophical ideas.

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