Wall Street’s foray into the mortgage origination business continued in earnest this week, as Morgan Stanley announced plans to purchase Virginia-based non-conforming loan specialist Saxon Mortgage. “The transaction supports Morgan Stanley’s strategy of building a global, vertically integrated residential mortgage business,” the investment bank said in a statement announcing the $760 million deal. “Saxon adds a premier servicing operation with a scalable U.S. origination platform to [our] ex-isting residential mortgage franchise...