Gene Dreams. Robert Teitelman. Harper, and Row, $18,95. If ever an industry was made to titillate Wall Street's "promiscuous imagination" (Teitelman's smart phrase, and one of many in this lively, sharply-drawn book), biotechnology was it. It roared out of the laboratory at a time when America's industrial selfimage was in shards. it was jazzy. It reflected the heat and light of the great entrepreneurial revolution just before it, in electronics. And it made promises. Oh, what ...