Identification of a novel beta cell glucokinase (GCK) promoter mutation (-71 G > C) which reduces promoter activity by Gasperikova, D, Tribble, N, Stanik, J, Huckova, M, Misovicova, N, van de Bunt, M, Kuklisova, L, Barrow, B, Barak, L, Dobransky, R, Bereczkova, E, Colclough, K, Ellard, S, Klimes, I, Gloyn, A