The case presented here may be the first fully identified and verified case of translocation 4p− syndrome, a B4/G22 translocation, ie, 45,XX,−4,−22, + t(4q 22q). Thirty-nine other cases of the 4p− syndrome, including one other possible translocation case, have been found in the medical literature. Conventional chromosome studies cannot distinguish between 4p− (Wolf) syndrome and 5p− (cri-du-chat) syndrome, and the clinical features, as in our case, may not be sufficiently characteristic to permit differentiation. The newer chromosome banding techniques have made specific identification possible.