Whereas the developmental defects caused by the absence of CHMP1A—microcephaly, cerebellar hypoplasia, and short stature—highlight the importance and widespread function of EV-mediated cellular communication during development, the persistence of ART-EVs in the adult human CSF suggests that there may be continued requirements for EV-mediated growth factor secretion in adult brain. The gene discussed is CHMP1A; the disease is microcephaly.