• A $3 M project aims to image an entire mouse connectome at synapse-level resolution by labeling ~120 distinct cell-surface receptors with DNA-tagged aptamers and scanning the intact brain with synchrotron X-ray tomography; open challenges include clearing the aptamers post-imaging, handling multi-exabyte data streams, and multiplexing 120 molecular labels without spectral overlap.

• Participants questioned whether receptor-density maps alone can reveal true synaptic connectivity, noting that overlapping dendrites and the lack of direct synapse-to-synapse labeling leave ambiguity; alternative “Rosetta Brains” schemes using DNA/RNA barcoding followed by fluorescent in-situ sequencing (FISSEQ) were proposed, citing the May 2016 bioRxiv pre-print “High-throughput mapping of single neuron projections by sequencing of barcoded RNA.”

• Technical trade-offs in high-resolution brain imaging were discussed: focused-ion-beam (FIB) milling offers finer cuts than mechanical knives but is slower and more expensive; dual-beam FIB-SEM systems remain consumable-intensive, while SWITCH proteomic imaging and saturated EM reconstruction (Cell 2015) were highlighted as reference methods.

• A “molecular recorder” concept was outlined in which neurons release DNA barcodes into the bloodstream; nanopore arrays implanted near the heart could continuously sequence these barcodes, creating a non-invasive, high-throughput log of neural activity, as proposed in a 2015 IEEE paper.

• George Church’s lab plans CRISPR longevity trials that will first deliver “youth genes” to aged mice and then to 28- to 30-year-old Arabian mares (biological age ~80 human years) to demonstrate large-animal rejuvenation, marking a step toward human applications.