The SNPs are intronic with unclear function. Evidence suggests that some VEGFA introns contain transcription factor binding sites and these areas may be important in the regulation of VEGF production and/or influence splicing (10). Therefore, it seems possible that the SNP-2 and SNP-3 (or other variants in LD with them) may alter VEGF expression in the hippocampus, which then influences hippocampal development, and/or plasticity in adulthood. Of note, the specific cytoarchitectural contributions, such as differences in neuronal size or packing density, to the morphological changes cannot be concluded from these neuroimaging data (11). Although VEGF has direct effects on neurogenesis, it also has effects on astroglia and endothelial cells (6) and thus changes in these cell populations may also contribute to the morphological changes.
