gene expression data from rodents are often of higher quality, as fresh tissue can be more readily obtained and gene expression data cluster by cell type in different species, rather than by different cell types in the same species [8]. Although we believe that mouse scRNA data are suitable to apply to human GWAS data, there are limitations, e.g., less conserved brain regions might contain cell types that express genes differently; cell types could be specific to certain species (on the other hand, it has been shown that gene expression in the brain, including key gene expression patterns, is well conserved across species [32]); and cell types could have different functions or could be connected to and active in different brain circuits.
