The authors report a case regarding a 7-year-old girl affected by short height, bone growth delay, lipidic alterations (hypercholesterolemia, hypertriglyceridemia and high apolipoprotein B values) and by a partial duplication of the short arm of the third chromosome: 46,XX, dup(3)(p26-pter). This chromosomal alteration appears "de novo", as the parent's karyotypes are normal and none of the patient's next of kin showed evidence of lipidic anomalies. The patient's short height and slight frontal bossing were the only features that could be described as typical of the dup3p syndrome.