Ulnar Mammary syndrome and TBX3: expanding the phenotype.

We present a patient with features of Ulnar Mammary syndrome (UMS) consisting of bilateral ulnar defects, inverted nipples, short stature with associated growth hormone deficiency, and cryptorchidism. Our patient also had a hypoplastic anterior pituitary and an ectopic posterior pituitary gland, ventricular septal defect (VSD), and cardiac conduction defects consistent with Wolff-Parkinson-White (WPW) syndrome. Although TBX3 is known to be expressed in both the developing heart and the pituitary gland, conduction defects and anatomical pituitary abnormalities have not been previously described in UMS.