Although ARHGAP11B has not been the focus of microcephaly studies in the past, it should be noted that, due to its high sequence homology to ARHGAP11A, mutations in ARHGAP11B in microcephaly patients were perhaps masked by ARHGAP11A. As some cases of 15q13.3 microdeletion display microcephaly and ARHGAP11B is close to one end of the deletion, it would be important to (re-)analyze 15q13.3 microdeletion cases with microcephaly in detail to see if ARHGAP11B is perhaps affected by the deletion. Here, ARHGAP11B is linked to microcephaly.