3 ms·
On the assumption that there are big areas that can be skipped or deleted without any effect on the phenotype though, I've often wondered why there doesn't seem
by tragomaskhalos 4y ago
On the assumption that there are big areas that can be skipped or deleted without any effect on the phenotype though, I've often wondered why there doesn't seem to be evolutionary pressure to delete them. Is it that the energy or other costs of duplication of those regions are not significant, or are there other factors that oppose it?
- dkural 4y agoIt's exactly as you say it - the energy costs are negligible. Most mutation is neutral drift.
- rolph 4y agoDNA, and many other biological polymers are structure as well as storage, some of these regions are about structure and modification of structure, to facilitate modality of function. they act as recognition sites, consensus sequences, torsion limiters, process interference selectors, user defined variables. picture if you will, a big mass of magtape, no spool just a disaster, and you have to scan accross this mess until you find an accessible loop of it with a particular flag or type readable- likehow magtape works, except you have the mechanical challange of reading the tape in the form of a quivering, dynamic mass of spaggetti being read at mutiple locations and having to remain undamaged. some of these regions make the biggest contribution by simply allowing mechanical slack and positioning of contact sites.
- naniwaduni 4y agoYou can't have an evolutionary pressure to delete stuff in general, because then you'll oops out stuff that needs to be there. Short of that, building the mechanisms to figure out what to delete would be far more short-term expensive than copying everything around for one more generation.