Quote:Remember from biology class: your DNA carries the instructions for building all the proteins your body needs. Those instructions are organised into 46 chromosomes — long threads of DNA wound tightly around scaffolding proteins. The whole bundle lives inside the nucleus, a tiny compartment in the centre of each cell.

The classic textbook view of the genome is one-dimensional: a long line of letters that scientists try to read end-to-end. But the genome is not a line. When folded into the nucleus, two stretches of DNA that sit far apart on the linear sequence can end up nose-to-nose. The folding is not just space-saving; it is part of how the genome works. Genes that need to be turned on together get folded into the same neighbourhood. Genes that need to be switched off get banished to a different one.
Think of the nucleus as a vast library. If each chromosome were a book:

• The first dimension is simply the letters in each book.
  
• The second dimension represents the many thousands of cross-references within and between the books.
  
• The third dimension is way the books are arranged on the library shelves.
  
• The fourth dimension is time. Think of it like the books on the shelf are being moved throughout the day. However, the fourth dimension involves changes to the letter string, the cross references, and the arrangement of the books.
  

At the end of the 20th century, biology only had access to the 1st dimension. The new paper is a snapshot of all four, in much higher resolution than we have ever had.
What the new study found
The 4D Nucleome Project combined six different mapping techniques and applied them to two well-studied human cell lines. The headline numbers are striking:

• Over 140,000 specific looping contacts were catalogued per cell type. Each loop is a place where two distant stretches of DNA reach across the nucleus and touch each other, and each one does a particular job.
  
• Six functional classes of loops were identified, including loops that turn nearby genes on, loops that hold genes ready for future activation, and loops that act as boundaries between genetic neighbourhoods.
  
• Nine distinct spatial compartments were identified inside the nucleus. Active genes cluster near the interior, where the cell’s protein-making machinery is concentrated. Silenced genes are pushed out to the wall.
  
• The folding pattern can be predicted from the DNA sequence alone. That is, you can read the linear letters and work out, in advance, how the genome will fold in 3D.
  

That last finding is the kicker. It means that the instructions for how the genome folds are encoded in the genome. The 1D code specifies the 3D shape. The 3D shape governs which genes get used in 4D. And the whole arrangement updates itself as the cell changes state.

(14-06-2026, 03:19 PM)Altruist Wrote: "theory" = "a bunch of unproven hypotheses"

Quote:

Animals, even insects, can create designs that extend beyond the kinds of design produced by the forces of nature alone. Animal designs typically have the added hallmark of functionality — for example, a beehive, or a bird’s nest, or a spider’s web. However, these designs seem to be pre-programmed or instinctive, and do not originate from the individual creativity of the animal.

1. How did the information required to instantiate the design arise in the first place?
   
2. How did the information for the design become coded within the biochemistry of the organism?
   
3. How did an effectual, multi-generational information storage, retrieval, and implementation system come to exist within the living creature’s being?