Other VDR polymorphisms that have been associated with TB meningitis include Taq1 and Apa1 [42, 43] A possible mechanism for these findings could be that single nucleotide polymorphisms (SNPs) in VDR genes, including Fok1, can modulate expression of vitamin D which may in turn have downstream immunologic effects [44]. This evidence concerns the gene VDR and meningeal tuberculosis.