The T allele of a single-nucleotide polymorphism 13.9 kb upstream of the lactase gene (LCT) (C-13.9kbT) does not predict or cause the lactase-persistence phenotype in Africans. by Mulcare, C, Weale, M, Jones, A, Connell, B, Zeitlyn, D, Tarekegn, A, Swallow, D, Bradman, N, Thomas, MG