The More muscle you have, the more you can drink. Fat doesn't help that much in metabolizing liquor. That's the reason why men can usually drink more than women; men have *proportionally* more muscle mass than women.
Drinking more constantly boosts your alcohol tolerance, because your liver gets stronger from processing that poisonous liquor.
Asian people generally have low fat and muscle mass. But the same study also said that Native Americans have some of the highest tolerances, so I doubt that's true...