Two live-born children and one fetus were found to be affected by autosomal imbalance consisting of a partial duplication of the long arm of chromosome 5 (5q33→qter) and partial deficiency of the short arm of chromosome 8 (8p23-pter), resulting from segregation of a paternal translocation heterozygote t(5;8) (q33;p23). The phenotype of the children was rather similar to that of the fetus. The main features included Craniofacial dysmorphia consisting of downward slant of eyelids and corners of the mouth, flat and widened nasal bridge, prominent philtrum, and small mandible. Ventricle and atrium septum defects were associated with overriding aorta and right heart hypertrophy in all three. Statomotoric retardation was evident postnatally in the two children. This observation indicates that structural autosomal imbalance may produce a fetal phenotype that is specific for the karyotype and comparable to that seen in the newborn.