[A newborn infant with the xxxxy-syndrome].

In a three weeks old infant with dysmorphic features a 49, XXXXY karyotype was demonstrated from chromosome preparations of lymphocytes. In the literature only a few newborn infants have been described with this syndrome. The most frequent symptoms of the syndrome in older patients are mental retardation, dysmorphic signs, hypogonadism and skeletal malformations. In our patient we found a low birth weight, a peculiar facies, in addition to a patent ductus arteriosus, a scoliosis and normal external genitals. The most typical skeletal malformations may develop at a more advanced age.