Anophthalmia and microphthalmia are etiologically and clinically heterogeneous. We present a 13-year-old boy with microphthalmia and multiple anomalies who was evaluated as part of our research into the etiology of microphthalmia. His clinical features included left microphthalmia, persistent hyperplastic primary vitreous and posterior coloboma, right posterior pole coloboma, pectus excavatum, mild hypotonia, mild delays in speech and motor development, and an anxiety disorder with social difficulties. Investigations with a chromosome microarray revealed a de novo deletion of chromosome 16p11.2 of approximately 882 kb in size. Deletions of this region of chromosome 16p11.2 are a newly delineated microdeletion syndrome, but this is the first report of microphthalmia and coloboma associated with monosomy for 16p11.2, and emphasizes the clinical variability that can be present with this deletion. This report contributes to the growing knowledge regarding this microdeletion and suggests that rare copy number changes may be a cause of microphthalmia and other eye anomalies. © 2010 Wiley-Liss, Inc.