They are sisters, but one wouldn't know it. As Julie moves down the hall in her wheelchair, passing a constantly pacing Amy, there's no eye contact or sense of recognition.

Amy Bishop, at 36, has beautiful, dark brown eyes that seem alternately cunning and vacant. Her hair is thick and slightly wavy, but gray is overtaking the dark brown strands. She doesn't curl it now and sometimes forgets to comb it. She's gaining weight and no longer fusses over her clothes, choosing instead to wear a pair of baggy jeans and a slightly rumpled shirt. She seems much older than her years, angry and somehow depleted.

Julie Askew, 29, smiles more often, a perpetual lift at the corner of her mouth. Her eyes, too, are deep brown. But they seem to smile. She's rail thin, wasted first by a car wreck when she was 20 and more recently by the disease that is eating away her mind and body.

Amy can speak but seldom does. Julie loves to talk but is hard to understand, as if the consonants that frame the vowels have disappeared.

They are both sisters and strangers, watching their young lives wind down inside nursing homes, held prisoner by a disease that will eventually rob them of their ability to think, to communicate, to move. It will weaken them. When they are most vulnerable and frail, an opportunistic illness like pneumonia will kill them.

Then, the disease will go after Amy's children.

· · · · ·

Huntington's is a hideous disease. Formerly called Huntington's chorea (from the Greek word for "dance" for the jerky motions it can cause), it is marked by progressive degeneration from inside the brain. Certain brain cells waste away. Symptom severity depends on how many cells are lost.

Physicians dropped the word chorea because it implies that the dancelike movements are an integral part of the disease. Many people, however, don't have that symptom. The diagnosis was being missed.

At its worst, the disease has been compared to having Alzheimer's, multiple sclerosis and Parkinson's diseases simultaneously.

Most cruel of all, doctors say that people with Huntington's retain their memories of who and what they were before. But it destroys the ability to reason, to communicate, to focus.