DNA methylation of vitamin D genes: A connecting link between vitamin D levels and grade of SARS-CoV-2 infection

Abstract

Background: The mechanistic relationship between the methylation process of the vitamin D gene and its impact on vitamin D levels and COVID-19 infection severity remains a subject of ongoing investigation. However, the lack of vaccines and targeted treatment in the initial phase of the pandemic had stimulated considerations regarding the potential use of vitamin D as a strategy for managing the disease. Vitamin D genes regulate vitamin D synthesis through epigenetic changes such as methylation, which affect various gene expressions. Aim and Objectives: The present study aimed to establish the relationship between vitamin D gene methylation in COVID-19 patients and vitamin D deficiency and the severity of COVID-19 symptoms. Material and Methods: Fifty RT-PCR confirmed SARS-CoV-2 patients were cross-sectionally evaluated, after ethical approval and informed consent, for severity of covid infection, serum levels of vitamin D along with other blood parameters and percentage of vitamin D gene methylation. ANOVA and correlation coefficient were used for statistical analyses with 'p' value <0.05 being considered significant. Results: There was no significant correlation between plasma vitamin D level and vitamin D gene methylation (CYP27B1 and CYP24A1) although there was significant correlation among methylation status of Vitamin D genes. This study revealed that the SARS-CoV-2 infection grades were significantly correlated with the degree of methylation of the vitamin D genes. Conclusion: Our study concludes that the percent methylation of the vitamin D genes and the interplay between these genes may determine vitamin D levels and COVID severity. In future, confounding factors that could influence the methylation (e.g., age, pre-existing health conditions, vitamin D supplementation) also should be considered.

Keywords

• covid-19
• vitamin d deficiency
• vitamin d genes
• methylation