Over the age of 9 and still waiting for that letter from Hogwarts? Andrea Trying may have an answer to why you haven’t gotten one. This Harry Potter superfan has decided to formulate a genetic theory of witches and wizards in response to J.K. Rowling’s claim that the wizarding gene is dominant. In true Internet nerd fashion, she posted her findings on Tumblr and sent it off to the author herself. A love of Harry Potter combined with a penchant for intellectualism in your freetime? I think I’m in love. You can check out the full paper here. Warning: contains science.