Background The correlation between vitamin D and the immune system began with the discovery of the VDR and CYP27B1 genes in almost all immune cells including T cells, B cells, neutrophils, macrophages and dendritic cells. The CYP2R1 rs10741657 and CYP27B1 rs10877012 genes have a quite important role in the vitamin D metabolism process starting from pre-vitamin D3 to 25(OH)D3 and then metabolized again to the active form 1,25(OH)2D3. Disruption of this cytochrome enzyme can reduce the concentration of 25(OH)D3.

Objective Research that examines the correlation between biomolecular aspects of the CYP2R1 and CYP27B1 enzyme coding genes with blood serum 25(OH)D3 concentrations in a healthy population in Jakarta.

Method This research uses an analytical observational study design with a cross-sectional study method. The independent variables are the CYP2R1 rs10741657 and CYP27B1 rs10877012 genes. DNA genotyping from blood using the polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) method on 95 samples. DNA visualization using electrophoresis and gel-doc techniques. The dependent variable is the concentration of 25(OH)D3 which was measured using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Statistical analysis was carried out using SPSS 22.

Results The mean concentration of 25(OH)D3 for the group with the mutant genotype (AA) was 19.15 ng/mL + 19.61 indicating lower levels compared to the non-mutant genotype (GA/GG) with a mean concentration of 25(OH).)D3 32.41 ng/mL + 30.33 and 21.21 ng/mL + 18.39. The CYP27B1 rs10877012 mutant (GG) genotype had a mean 25(OH)D3 concentration of 23.58 ng/mL + 16.36, which was also lower than the 25(OH)D3 concentration of the non-mutant group (GT/TT) with a mean concentration value of 25(OH)D3 for the GT genotype 26.67 ng/mL + 20.87 and the TT genotype with a concentration of 29.27 ng/mL + 32.45. Analysis of the correlation between the CYP2R1 rs1074165 gene polymorphism and 25(OH)D3 concentration p value = 0.022, while the CYP27B1 rs10877012 gene polymorphism with 25(OH)D3 concentration obtained p value = 0.735.

Conclusion There is a significant correlation between the CYP2R1 rs10741657 gene polymorphism and 25(OH)D3 concentration, while the CYP27B1 rs10877012 gene polymorphism does not have a significant correlation with 25(OH)D3 concentration.

The authors have declared no competing interest.

This study was funded by Atma Jaya Catholic University of Indonesia

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

All research procedures have received ethical approval from the research ethics commission of the Faculty of Medicine and Health Sciences, Atma Jaya Catholic University of Indonesia with number 23/09/KEP-FKIKUAJ/2023 on September 24th 2023.

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