A key goal of this study was to prioritize specific cell types for follow-up experimental studies. As our metric of gene expression specificity was computed based on all cell types in the nervous system, it is possible that the most specific genes in a given cell type capture genes that are shared within a high level category of cell types (e.g. neurons). To rule out this possibility, we computed new specificity metrics based only on neurons from the central nervous system (CNS). We then tested whether the top 10% most specific genes for each CNS neuron were enriched in genetic association for the brain related traits that had a significant association with a CNS neuron (13/18) in our initial analysis.
