Association between partial remission phase in type 1 diabetes and vitamin D receptor Fok1 rs2228570 polymorphism.

Objectives: The aim of the current study was to assess the natural course of partial remission (PR) phase of type 1 diabetes (T1D) and to highlight the putative association between vitamin D receptor (VDR) (Fok1) gene polymorphism and PR phase.

Methods: Ninety participants with newly diagnosed T1D were followed up for a total of 12 months. The VDR (Fok1) rs2228570 gene polymorphism was genotyped using allelic discrimination (AD) assay.

Results: Fifty-four patients (60 %) reached PR with an average duration of 5.63 ± 2.9 months. Among remitters, the frequency of CC "FF" genotype and allelic frequency of C "F" were significantly higher (p<0.001). Furthermore, participants expressing "CC" genotype had earlier onset of PR and spent a significantly longer duration in remission (p<0.001). Younger age (p<0.001; OR 41.6; CI 12.12-142.99), absence of DKA (p<0.001; OR 16, CI 4.36-50.74), higher C-peptide levels (p<0.001; OR 19.55; CI 6.52-58.63), and presence of CC "FF" genotype of VDR (p<0.001; OR 6.74; CI 2.41-18.86) best predicted the overall occurrence of PR.

Conclusions: Younger age, less extent of metabolic derangements, and expression of a CC "FF" genotype were found to influence the occurrence of PR. Data from the current study showed that the "C" allele could have a protective role on preserving residual β-cell mass and could predict both onset and duration of PR among newly diagnosed T1D. These findings support the growing concept of future tailored precision medicine.