In our current study, there was no significant difference in the BDNF Val66Met polymorphism between T2DM and the controls, which is consistent with a study in a Caucasian population in Denmark [22] and in a Chinese population [24], suggesting that the BDNF Val66Met polymorphism may be not associated with susceptibility to T2DM directly. Here, BDNF is linked to type 2 diabetes mellitus.