Few real nightmares on earth compare to the terror wrought by Alzheimer's disease. That this fatal brain disorder not only annihilates a person's mind, but starts doing so years before it takes their life is surely its most insidious aspect. Its initial symptoms of forgetfulness and personality changes lie so close to normalcy that they typically go unnoticed; and, once noticed, too long unexplained. As the victim's grasp further slides, it can bring nothing but tormenting confusion for both the patient and those close to him. What can be worse than watching someone you love cognitively flailing, until eventually they no longer recognize faces, surroundings, or even themselves?

More razor-sharp than Alzheimer's physical distress is this emotional pain felt by patient and helpless bystanders. "No one not saddled with it can understand it, not even my best friend," says Julie Noonan-Lawson. Along with her four sisters and five brothers, Julie watched their mother Julia Tatro Noonan succumb to a rare form of Alzheimer's that strikes in middle age and is passed down to 50 percent, on average, of offspring. Consequently, all ten of Julia's children, who currently span the ages of thirty-six to fifty-eight, bear the burden of being genetically at risk.

Framed in their recollections of their mother is how much she loved to sing. Growing up, they would cram into the family station wagon on hot summer days, swimsuits in tow, and led by Julia's strong lilt sing one song after another full throttle all the way to Manomet Beach on Massachusetts' South Shore. When, in her early forties, Julia inexplicably began singing less and lapsing into depressed moods, her children followed her into a mire of anxiety, trouble, and hurt. Her lost song was their lost song.

The Noonans' response to the disease has been to not take it sitting down. So admirably, they and hundreds of other at-risk families have made invaluable contributions to research, helping the thousands of us who make up the Alzheimer's scientific community to try to extrapolate the disorder's molecular roots. Without their aid, the following account of the inestimable progress we've made in a remarkably short time wouldn't exist for the telling. Faced with the prospect of the disease's . . .