Mitchell Levine, managing director and head of whole loan trading at Credit Suisse First Boston, has been removed from the desk as part of the firm's investigation into a loss of at least $40 million in its mortgage-backed trading book, according to a firm official. Levine did not return calls or an e-mail. It could not be determined if and when Levine will return to the desk. The move comes shortly after Michael Flannelly, a whole loan trader, was removed from the desk as CSFB officials conducted a forensic investigation into whole loan trading activities (BW, 3/22). He remains off the desk, while still being a firm employee. The CSFB official said the sidelining of Levine is related to the investigation but stressed that Levine, too, remains at the firm. John Gallagher, spokesman, declined to comment.