SLCO1B1 and tuberculosis: Similarly studies by Chigutsa et al. (2011) and Gengiah et al. (2014) on the SLCO1B1 (rs4149032) SNP both reported an associated between high SNP frequency and low rifampin plasma concentrations in TB and HIV-TB co-infected South African individuals taking rifampin (Chigutsa et al., 2011; Gengiah et al., 2014).