We examined a girl presenting neuropsychomotor developmental delay and multiple malformations including antenatal and postnatal growth retardation, congenital heart defect, and facial dysmorphisms. Cytogenetic analysis was performed on peripheral blood lymphocytes with the GTG-banding technique, which revealed an unbalanced translocation: 46,XX,der(13)(13pter→13q34::3p24→3pter)pat. Karyotype analysis of the father demonstrated a balanced translocation, 46,XY,t(3;13)(p24;q34), indicating the inheritance of the derivative chromosome 13. The mother karyotype was normal. We suggest that most of the structural malformations seen in this patient are due to the 3p trisomy, while the neuropsychomotor alterations are a consequence of both chromosome aberrations.