Preheat oven to 400 degrees. Combine cranberries and 1/4 cup sugar; let stand 15 minutes. Combine remaining sugar and biscuit mix in bowl; blend well. Beat egg in small bowl; add yogurt. Add to biscuit mixture; stir until dry ingredients are moistened. Fold in cranberries. Fill well greased muffin cups 3/4 full. Bake 25 minutes.