American Home MBS Classes Downgraded

Four classes from two issues of American Home Mortgage Assets Trust residential mortgage-backed certificates have been downgraded by Fitch Ratings. The downgrades were as follows: series 2005-1 group 3, class 3-M-4, from BBB-minus to BB (and remains on Rating Watch Negative); and series 2005-2 group 1, class 1-B-3, from BBB-plus to BB (and placed on Rating Watch Negative), class 1-B-4, from BB to CC/DR3, and class 1-B-5, from B to C/DR6. Fitch also placed class 3-M-3 of series 2005-1 group 3 on Rating Watch Negative and affirmed the ratings on 21 classes in four American Home deals. The downgrades were attributed to deterioration in the relationship between credit enhancement and expected losses.