Use of human neuronal cells derived from iPS cells to examine gene expression profiles may only model the transcriptome of embryonic or early stage immature neurons. It is possible to also have variable expression patterns of certain loci located within a specific chromosome, which could hinder the number and certain types of transcripts that can be assayed for expression changes. Furthermore, it is imperative to drive differentiation of iPS cells to a specific cell type (excitatory versus inhibitory) that is appropriate for the hypothesis being tested. However, we argued above that the beauty of reprogramming technology is the ability to model disease using patient-derived iPS cells to accurately model human neuropathology. Nevertheless, the following points need to be considered to model AUDs using human neuronal cells: 1) Does forcing a neuronal lineage to a certain cellular subtype (excitatory or inhibitory) accurately model the environment that human neurons reside in? 2) iPS cell technology is expensive and time consuming and for this reason some studies are limited to testing a single concentration of drug because of the increasing financial strain assaying
