Features include a long face with telorism,
microretrognathia, arachnodactyly, and a short stature. Visual impairment,
sensorineural deafness, laterally overlapping upper eyelids, nystagmus, large
corneas, abnormal auricles, cryptorchidism, hypospadias, and spasticity. Anodontia
or oligodontia are frequent features. Multiple pigmented nevi can be observed.
Sometimes the patient presents with abnormal vertebrae and moderate-to-severe mental
retardation. Patients may develop lymphoblastic leukemia with a mediastinal mass and
leukemic infiltration of tissues.