We performed chromosome microdissection in order to define the "de novo" rearrangement observed in a female patient affected by: frontal microgyria, mild psychomotor retardation, thoracic scoliosis, XIIth rib asymmetry and facial dysmorphisms. Through the use of the micro-FISH we evidenced a deletion of the 3p25pter region and a 4p16.1 duplication. We performed a karyotype-phenotype correlation in our patient and in the ones previously reported in literature which had a 3p25pter deletion or the 4p16 duplication.