1. Heat oven to 350 degrees Fahrenheit. Grease bottom of one 9x5-inch or two 8x4-inch loaf pans with shortening.
2. In large bowl, stir sugar, butter, eggs, bananas, and buttermilk until mixed. Stir in flour, baking soda, and salt just until moistened. stir in blueberries. Pour into pan.
3. Bake 9-inch pan about 1 hour and 15 minutes, 8-inch pans 55 to 60 minutes, or until toothpick inserted in center comes out clean. Cool 5 minutes. Loosen sides of loaf from pan; remove from pan to wire rack. cool completely, about two hours, before slicing. Wrap tightly and store at room temperature up to four days, or refrigerate up to ten days.