Studies have shown that students have been more willing to take this rice purity test than to take a very private STD test because they felt the purity test results were more of a no judgement zone.
Russians come from a plethora of different people, but Slavs are the most common. Slavs traditionally have light brown or even blond hair, with only a smaller part of them endowed with dark hair from southern ethnicities, like so: Black hair color is actually pretty common, especially the further you go East.
It is caused by a variation in the Mc1r gene and is recessive. Red hair has the highest amounts of pheomelanin, around 67%, and usually low levels of eumelanin. At 1-2% of the population, it is the least common hair color in the world. It is most prominently found in Scotland, Ireland, Wales and England.