VDR and systemic lupus erythematosus: In SLE patients, VDR expression was 1.44-fold lower (2ΔΔCq = 0.69) in CT carriers and 1.73-fold higher in TT carriers, while in CS, the expression was 43.5-fold higher in CT and 83.6-fold higher in TT genotype carriers, compared to the CC genotype group (Figure 4e).