Preheat oven to 375℉. Grease a 12-cup muffin pan or line it with liners.
In a large bowl, whisk together the the flours, sugar, baking powder, salt, and ginger. Add the egg, yogurt and butter, stirring only enough to dampen the flour (batter should not be smooth). Add the blueberries and mix lightly. Spoon batter into the muffin pan, filling each cup about two-thirds full. Sprinkle tops with a little coarse sugar if you like.
Bake for about 20-25 minutes or until lightly browned. Remove from oven and let cool 10 minutes in the tin, then turn out onto a rack to cool completely.