RESUMO
Trisomy 9p syndrome was first described by Rethore, et al in 1970 and about 150 cases have been reported. Trisomy 9p has been reported as either partial or complete. The term "duplication 9p syndrome" instead of "trisomy 9p syndrome" is used since most of the reported patients had only partial duplication rather than the whole arm duplication of 9p. Duplication of 9p syndrome is characterized by growth and developmental retardation, microbrachycephaly, deep and wide set eyes with down-slanting palpebral fissures, "globular" nose, down-turned corners of the mouth, prominent apparently low-set ears, and short fingers and toes with small nails. A 10- month-old male was referred to our department of pediatrics because of hypotonia and delayed development. Karyotype revealed 46, XY, dup(9)(p12p24) by GTC-Banding. We report a case of a duplication 9p syndrome diagnosed by GTC-banding.