In medium bowl, mix flour, baking powder, baking soda, salt, sugar and orange rind together. Using a pastry cutter or two knives, cut the shortening into the flour mixture until it resembles coarse meal.
In small bowl lightly beat egg with fork. Add the buttermilk to the beaten egg, then add it to the flour mixture. Using a fork, stir until just moistened. Add the blueberries. Stir gently just to mix. Turn dough out onto floured surface or cloth and gently knead 3 or 4 times. Roll out to 1/2-inch thickness. Cut with biscuit cutter or into desired shapes. Place on lightly greased cookie sheet and bake at 400° F for 15 minutes or until golden.
Mix butter with sugar, cinnamon and nutmeg and brush onto tops of biscuits as they come from the oven.
Servings: 12 to 15 biscuits