Abstract: | We report on 2 patients with de novo proximal interstitial deletions of the long arm of chromosome 4: in one the deletion resulted in monosomy (4)(q21.3q23), in the other it produced monosomy (4)(q13.2q23). Review of 9 cases of deletions involving the 4q21/4q22 region reported previously detected a characteristic phenotype in S patients. This phenotype was present in our patients. We conclude that the deletion in the 4q21/4q22 region results in a specific clinical syndrome associated with central nervous system overgrowth that may be a result of anomalous imprinting in the 4q21/4q22 region. Am. J. Med. Genet. 69:400–405, 1997. © 1997 Wiley-Liss, Inc. |