Defining the phenotype in Floating Harbor syndrome
Floating Harbor syndrome (FHS) is a rare syndrome with the features of short stature, speech impairment, delayed bone age and dysmorphic facies. The diagnosis can be difficult as the dysmorphic features are subtle, and the cluster of features of short stature, delayed speech and delayed bone age is not infrequently encountered in clinical practice. Most published reports are of one or two cases. We define the phenotype in FHS by reporting clinical findings in 11 individuals with FHS ranging in age from 7 to 34 years. Photographs at different ages will be presented to aid recognition of the condition. The lateral profile of the face is characteristic and aided diagnosis. Significant behavioural problems, including hyperactivity, short attention span and aggressiveness were present in almost all of the individuals in the study. These problems improved in adulthood. Expressive speech was more affected than receptive speech, and mild learning difficulties were present in most patients. Supervised independent living occurred in the adult patients. Early puberty was noted. Palatal inco-ordination, hypernasal speech and submucous cleft palate were observed. Parents reported that the children tanned easily and some individuals experienced photophobia. Of the three adults, heights were in the range of 135-140cm for females and 150-155 for males. Molecular studies including sequencing of FOXP2 and micro-array CGH revealed no abnormality.
This study further defines the phenotype of FHS and should assist the clinician with this diagnosis.