SLC11A1 and tuberculosis: Background. To explore the potential role of natural-resistance-associated macrophage protein 1 (NRAMP1) gene, vitamin D receptor (VDR) gene, (human leukocyte antigen, (HLA-DRB1) HLA) -DRB1 gene, and HLA-DQB1 gene polymorphisms in susceptibility to tuberculosis (TB) in the Chinese Kazakh population.