Lightly spoon flours into dry measuring cups; level with a knife. Combine flours, sugar, baking powder, baking soda, and salt in a large bowl, stirring with a whisk. Combine buttermilk, oil, egg, and egg white, stirring with a whisk; add to flour mixture, stirring just until moist.
Heat a nonstick griddle or nonstick skillet coated with cooking spray over medium heat. Spoon about 1/4 cup batter per pancake onto griddle. Turn pancakes over when tops are covered with bubbles and edges look cooked. Serve with syrup and butter.
Keep cooked pancakes warm in a 200º oven while preparing remaining pancakes, then serve them with heated maple syrup.