Spina bifida occulta and kyphoscoliosis. Multiple basal cell carcinomas, melanin pigmentation, foci of calcification, affecting mainly the face, neck, upper trunk and, less commonly, the abdomen, lower trunk, and extremities. Subcutaneous calcification and epidermal cysts may be associated. Calcification of falx cerebri and tentorium cerebelli, cysts of the choroid plexus of the third and lateral ventricles of the brain, glial nodules projecting from the lateral ventricles, agenesis of the corpus callosum and communicating hydrocephalus, meningioma, cysts of the septum pellucidum, and medulloblastoma. Hypogonadism in males, cryptorchidism, horseshoe kidney, L-shaped kidney, kidney agenesis, duplication of renal pelvis and ureter, and calcified fibroma, carcinoma or fibrosarcoma of the ovaries.
Inheritance is autosomal dominant with variable expressivity.