Laurent Gauthier, former MBS analyst with the recently shuttered fixed income unit of Prudential Securities in New York, has joined Banc of America Securities in New York. He describes his new position as an " all-around MBS strategist," where he will concentrate on the pass-through and CMO markets. He will report to Sharad Chaudhary, the residential MBS research chief who is based out of Charlotte. Chaudhary says he is replacing former prepayment modeler Warren Xia, who recently left the firm. At Prudential, Gauthier reported to MBS research head Inna Koren. Prior to that, Gauthier was an MBS analyst at Goldman Sachs.