Chromosome 3 duplication q21 leads to qter deletion p25 leads to pter syndrome in children of carriers of a pericentric inversion inv(3) (p25q21).

Close phenotypic similarity between two cases carrying a rec(3) dup q,inv(3) (p25q21), 12 additional infants from the same inv (3)(p25q21) kindred who lived less than 1 year, and eight cases studied in other medical centers has led us to postulate the existence of a distinct chromosome 3 duplication-deletion syndrome. In the presence of trisomy for (3)q21 leads to qter and monosomy for (3)p25 leads to pter, the facial dysmorphy is unique: a distorted head shape due to irregular cranial sutures, thick low eyebrows, long eyelashes, persistent lanugo, distended veins on the scalp, hypertelorism, oblique palpebral fissures, a very short nose with a broad depressed bridge and anteverted nares, protruding maxilla, thin upper lip, micrognathia, low-set ears, and a short webbed neck. Port-wine stains, congenital glaucoma, cloudy corneas, cleft palate and harelip also occur frequently. Each infant has difficulty sucking and swallowing. Congenital anomalies of the cardiovascular system, of midgut rotation, and of the urogenital system are noted for the infants who died neonatally. Most frequent is a ventricular septal defect, followed by atrial septal defect, patent ductus arteriosus, patent foramen ovale, and coarctation of the aorta. Omphalocele, umbilical hernia, hyperplastic kidneys, polycystic kidneys, double ureter, hydro-ureter, hydronephrosis, and undescended testes often occur. The extremities are short in proportion to the length of the trunk. Clinodactyly, coxa valga, talipes, and spina bifida are frequently observed.