SEATTLE--Corixa, a development-stage biotechnology company founded here in 1994, announced that it will purchase the privately held, oncology-based functional genomics company GenQuest for $11.8 million--$4.5 million in cash. Corixa currently holds approximately 17 percent of the company's outstanding capital stock. GenQuest will consolidate its operations here and be fully integrated into Corixa. The combined entity will have approximately 100 scientific employees dedicated to discovery and early development of vaccines.