- A proposed in-vitro DNA synthesis system uses four engineered DNA polymerases, each selective for one nucleotide, that can be switched on/off by pH or other environmental cues so that a single “super-polymerase” molecule can be toggled between A, T, C and G incorporation modes.  
- Participants discussed splitting polymerase into a DNA-anchoring β-clamp-like “placeholder” module and a detachable catalytic module, allowing multiple polymerase variants to cycle on and off the same strand without permanent attachment.  
- A selection experiment was outlined: insert four altered polymerases plus a unique initiator sequence into an E. coli genome; survival or death signals would force evolution of a working DNA-writing pathway, effectively selecting for an entire in-vivo DNA synthesis system.  
- Mind-uploading alternatives to SENS-style longevity were debated, including Kurzweil/Moravec “gradual nanobot replacement,” Leitl’s 1990s Mind Uploading Research Group, and the idea of replacing neurons with engineered proteins that precipitate carbon-nanotube or graphene circuitry.  
- Backup of brain state was framed as a nanotech read-out problem: nanobots would encode synaptic connectivity and molecular state into organic “ID molecules” excreted in urine, or neurons could be engineered to self-report via DNA bar-coding and bacterial-style DNA shuffling (immunoglobulin VDJ recombination cited as precedent).  
- A cancer-therapy concept proposed engineering patient-specific recombinant B-cells that home to and attack brain tumors, leveraging the same targeting machinery used in monoclonal antibody production.  
- Rapid, laser-triggered polymerase control was defended for in-vivo DNA writing: dual-wavelength light provides both data input (sequence) and a precise clock signal, avoiding the slow kinetics of gene-product-based regulation.  
- Links and resources shared: Newcastle University double-degree programs in biotechnology and medical engineering; minduploading.org research archive; Eugene Leitl’s personal site; a 1998 review on immunoglobulin DNA rearrangement mechanisms.