Genetic predisposition to an impaired metabolism of the branched chain amino acids and risk of type 2 diabetes: A Mendelian randomisation analysis ανά Lotta, L, Scott, R, Sharp, S, Burgess, S, Luan, J, Tillin, T, Schmidt, A, Imamura, F, Stewart, I, Perry, J, Marney, L, Koulman, A, Karoly, E, Forouhi, N, Sjögren, R, Näslund, E, Zierath, J, Krook, A, Savage, D, Griffin, J, Chaturvedi, N, Hingorani, A, Khaw, K, Barroso, I, McCarthy, M, O'Rahilly, S, Wareham, N, Langenberg, C