Preheat oven to 375 degrees. Sift flour, baking powder, salt and soda into a bowl. Set aside. Cream shortening and sugar until light and fluffy. Add egg and sour cream. Mix well. Stir into flour mixture. Mix until well blended. Fold in raisins and currants. Spoon into a greased 2-quart casserole. Bake for 50 minutes. Cover with aluminum foil and baked 10 minutes longer or until done. Makes one round 8-inch loaf.