Deletion of the pseudoautosomal region in a male with a unique Y;13 translocation and short stature.

Short stature is a common finding in patients with Ullrich-Turner syndrome. Structural abnormalities involving the terminal short arms of the X and Y chromosomes have been shown to lead to short stature. A putative locus affecting height called PHOG/SHOX has been localized to a 170-kb critical region within the pseudoautosomal region (PAR). It contains a homeodomain and functions as a transcription factor. We have studied a 10-year-old boy with idiopathic short stature who was found to have a unique Y;13 translocation. Southern blot analysis using cDNA probes indicated that most of the PAR, including PHOG/SHOX, was lost as a result of this translocation. We conclude that haploinsufficiency for this gene is responsible for the growth failure in our patient. Treatment with recombinant growth hormone has resulted in greatly improved growth velocity.