ERBB2 and schizophrenia: Hsa-miR-449a shows a striking expression pattern during human pre-natal development,23 which may be related to ciliogenesis in the ventricular system,24 and hsa-miR-548d is involved in regulating the expression of erb-b2 receptor tyrosine kinase 2 (ERBB2), one of the receptors in NRG1–ErbB signaling pathways.25, 26 Thus, changes in the levels of expression of either miRNA could have long-term consequences for brain development and function, making it plausible for them to play a role in the etiology of schizophrenia.