Figure 1. Towards comprehensive classification of spinal neuron features.

Schematized in the top row are current perspectives on the classification of spinal neurons. Spinal neurons have traditionally been classified based on their morphology, biochemical properties, electrophysiological properties, embryonic origin, and connectivity. Recent advances in single-cell sequencing techniques, schematized in the bottom row, have facilitated high-throughput RNA-sequencing from thousands of cells in a given tissue. Patterns of gene expression can then be used to cluster cells into types. The unique molecular repertoire of each cell type mediates its functional features.