Pure de novo 17q25.3 micro duplication characterized by micro array CGH in a dysmorphic infant with growth retardation, developmental delay and distal arthrogryposis.

We describe a 3-year-old girl with pure 17q25.3 duplication and a complex clinical presentation comprising psychomotor/mental retardation, growth retardation and most dysmorphic features of partial duplication 17q syndrome with, additionally, a striking distal arthrogryposis. The duplication size was maximum 2.46 MB, being thus, to the best of our knowledge, the smallest 17q25.3 duplicated portion ever reported. This defect could only be detected by microarray assays, stressing once again the pertinence of this tool in detecting cryptic rearrangements. From the findings in the present patient and in the previously reported cases with duplication within the 17q21-7q25 region, it appears that the clinical features collected from the group of patients without a complementary monosomy illustrate better the trisomy 17q phenotype, and that most dysmorphic features of the 17q duplication syndrome might largely be related to the very terminal segment extending from 17q25.3 to 17qter.