Pulitzer winner Weiner (The Beak of the Finch) follows the Heywoods, a charismatic Massachusetts family rocked by middle son Stephen's diagnosis of amyotrophic lateral sclerosis, a.k.a. Lou Gehrig's disease. As 29-year-old Stephen battles its incurable, degenerative neural effects, older brother Jamie suddenly switches careers, from mechanical to genetic engineer, in a medical race to save his sibling. Weiner, whose own mother suffers from a similar ailment, writes an eloquent and engrossing story that's equal parts heartbreaking and hopeful -- a very human tale of superhuman will in a molecular world. The Heywoods not only explore the untested boundaries of gene therapy but also maintain faith when ''the odds against Jamie's plan were so long that...hope almost felt like the heavier weight.''