Researchers have discovered the genetic flaws that underlie a major type of glaucoma, a leading cause of blindness. By pinpointing what goes wrong, their finding may provide a basis for devising new treatments. The finding is part of a continuing wave of discoveries about the genes underlying common diseases. The wave began this spring as researchers reported the first results using a new device, DNA-scanning chips containing information on up to 500,000 genetically variable sites across the human genome. By comparing the genomes of patients with those of people in good health, researchers can identify which of the variable sites...