The daughter of patient 1 was born in 1964. Between the ages of 8 and 12 years, she was treated for short stature with injections of human growth hormone prepared from cadaver-derived pituitary glands. Some lots of the hormone she received were tested for prion protein and were found to transmit CJD to primates.4 She was neurologically asymptomatic until August 1995. Ataxia of gait and dysarthria progressed rapidly. In November 1995, James R. Miller, MD, found good cognition, severe dysmetria in all limbs, rigidity and spasticity, hyperactive tendon jerks, and bilateral Babinski signs. He noted no myoclonus. The results of brain magnetic resonance imaging and cerebrospinal fluid examinations were normal. The cerebrospinal fluid was tested in the laboratory of Paul Brown, MD, and showed the 14-3-3 protein.5 Dementia followed, and she remains in a long-term care facility. In August 1997, she was found by one of us (B.B.W.) to be mute and unresponsive to voice, bright light, noise, and visual threat. She had no startle responses or myoclonic jerks. Spontaneous and oculocephalic eye movements were of full range. The fundi and corneal reflexes were normal. Snout reflexes were active, but no pharyngeal reflex was elicited. No fasciculation was seen in the tongue. Her limbs were immobile and spastic, with flexion contractures at the knee and ankle. There was atrophy of distal leg muscles, and fasciculations were seen in the feet, gastrocnemius muscles, and quadriceps but not in the torso or arms. Tendon reflexes were overactive throughout, with bilateral Babinski signs and left ankle clonus.