In a large mixing bowl, whisk together the whole-wheat flour, raw sugar, baking powder, baking soda, and salt until evenly combined.
In a separate bowl, beat the egg lightly, then whisk in the buttermilk and the melted butter until mixed.
Pour the wet ingredients into the dry ingredients and stir gently until just combined; do not overmix—some small lumps are fine.
Preheat a nonstick skillet or griddle over medium heat and grease it lightly with butter.
Using a ¼-cup measure, pour batter onto the hot skillet for each pancake, then scatter a small handful of blueberries onto each pancake.
Cook until bubbles form on the surface and the edges look set, about 2–3 minutes, then flip and cook the other side for 1–2 minutes until golden and cooked through.
Serve the pancakes hot with pure maple syrup, if desired.