David's death may be a clue to a strange disorder
It had been his simple wish to walk barefoot on the grass and some day to live normally in the world. For this hope David, 12, and his family took the ultimate gamble: they traded the safety of a germ-free plastic bubble at Houston's Texas Children's Hospital for the slim chance that a bone-marrow transplant would allow the immunologically defenseless boy to live freely. Last week they lost their gamble, and his death was felt across the country.
David's case was unprecedented: no other human being had lived so long without a functioning...