VDR and vitamin D deficiency: The vitamin D receptor genotype of our patients was unknown, and one clinical trial has suggested that individuals with the tt genotype of the TaqI receptor polymorphism are more likely to respond to vitamin D supplementation.30 National ART protocols during the study dictated that most patients did not receive EFV, a drug previously associated with vitamin D deficiency.16 First-line ART recommendations for TB patients have since changed, and it is possible that the effect of ART on vitamin D metabolism varies by treatment regimen.