Preheat the oven to 200°C (392 °F).
Add the white rice flour, tapioca flour, corn starch, brown rice flour, xanthan gum, granulated white sugar, baking powder, baking soda, ground cinnamon, and salt in a bowl. Using a whisk, mix the ingredients until combined. Then, add the cubes of cold butter and work the butter into the flour mixture using your hand or a pastry cutter until the butter is pea-sized. Do not overwork the butter as you don’t want it to melt. Refrigerate the flour and butter mixture while you work on the next steps.
In a separate bowl, add the buttermilk, vanilla extract, egg, and blueberries. Using a whisk, combine the ingredients. Now, remove the flour mixture from the fridge and add it to the buttermilk mixture. Using a spatula, combine the ingredients until you have a dough-like consistency. The dough will be crumbly and sticky.
Transfer the dough into a floured working surface and shape the dough into a 2 cm (2/4 inch) thick disc. Using a knife or dough cutter, divide the dough into 8 equal wedges. Arrange the scones on a baking tray aligned with parchment paper 2 cm apart (1 inch).
Bake the scones for 12-15 minutes or until the edges, and the top is slightly golden. Let the gluten free blueberry scones cool down on the baking tray for 10 minutes before transferring them to a cooling rack.