Heat oven to 400 degrees. Grease bottoms of 12 medium muffin cups or line with paper baking cups.
Beat egg; stir in milk and oil. Mix in remaining ingredients except blueberries just until flour is moistened (batter will be lumpy). Fold in blueberries. Fill muffin cups 2/3 full. Bake until golden brown, 20 to 25 minutes. Immediately remove from pan. Yields 12 muffins.