Background: Vitamin D (Vit. D) is used extensively during tuberculosis treatment. Low levels of serum Vit. D increase the risk of active tuberculosis development. Altered expression of the proteins involved in Vit. D metabolism impairs cathelicidin production, thereby increasing the host susceptibility to tuberculosis.
Objective: We are trying to investigate whether single nucleotide polymorphisms (SNPs) in LRP2, CUBN, and VDR genes could affect tuberculosis development.
Methods: We included participants of the Korean Association Resource (KARE), part of the Korean Genome and Epidemiology Study (KoGES), and used their recorded data. A total of 8840 people (4182 men and 4658 women) were eligible subjects. The 5-kb regions from the ends of transcripts of GC, LRP2, CUBN, and VDR genes were amplified to select 13, 47, 70, and 15 SNPs, respectively. For association analysis and statistical analysis, PLINK version 1.07 and PASW Statistics version 18.0 were used.
Results: Significant correlation was observed in 11, 2, and 1 SNPs in LRP2, CUBN, and VDR genes. The effect of rs6747692 of LRP2 on transcription factor binding was confirmed using RegulomeDB. We confirmed that rs2239182 of VDR is located in the genomic eQTL region and can affect transcription factor binding and gene expression.
Conclusions: Genetic polymorphisms in genes encoding proteins involved in Vit. D metabolism influence immune system components. Therefore, such polymorphisms may influence the susceptibility to Mycobacterium tuberculosis invasion and alter the defense mechanisms against Mycobacterium tuberculosis infection. The correlation between genetic variation and tuberculosis development can provide new guidelines for the management of tuberculosis.
Keywords: CUBN; LRP2; Polymorphisms; Tuberculosis; VDR.