Interstitial 6q duplication in an adult male without growth delay or severe mental retardation.

We report on a 28 year-old male with peculiar facies, distal joint contractures and other multiple congenital anomalies. Cytogenetic analysis by G banding revealed a distal tandem interstitial duplication of the long arm of chromosome q6, dup.(6)(6q24.2-->q26). This chromosome abnormality was confirmed by fluorescence in situ hybridization with total chromosome 6 painting. This is probably the second documented case of 6q duplication without growth retardation or severe psychomotor retardation. The clinical findings in our patient are similar to that of whistling face syndrome (WFS) and, in fact, he was diagnosed with WFS as a child. The literature were reviewed and the phenotypic features of this patient were compared with those previously reported for both duplication 6q and whistling face syndromes. There is a significant overlap between the phenotypes of these two syndromes. Careful evaluation of the terminal end of the 6q in cases suggestive of WFS might be warranted.