Kevin McKernan was leading Life Technologies Corp. (LIFE)’s Ion Torrent DNA-sequencing research when a new business opportunity caught his eye: marijuana. A year later, McKernan, 38, has quit his job, formed a startup run from his house in Marblehead, Massachusetts, and announced today that the company had sequenced the entire genome of the cannabis plant. The project, which cost about $200,000, may lead to the development of treatments for cancer, pain and inflammatory diseases, he said. McKernan’s company, Medicinal Genomics, is making the data public using Amazon.com Inc. (AMZN)’s EC2 cloud- computing system. McKernan called the work a “draft assembly,” and it hasn’t yet been published in a peer-reviewed academic journal.