This meta- analysis concludes that hypovitaminosis D is associated with increased risk of hyperglycemia both in diabetic and non-diabetic subjects .
There is evidence that vitamin D status is associated with type 2 diabetes .
Many observational studies have been performed investigating the relationship of vitamin D status and circulating biomarkers of glycemic regulation .
To find out whether this association holds , we conducted a systematic review and meta- analysis of cross sectional and longitudinal studies .
A genome-wide methylation study of severe vitamin D deficiency in African American adolescents.
OBJECTIVES To test the hypothesis that changes in DNA methylation are involved in vitamin D deficiency-related immune cell regulation using an unbiased genome-wide approach combined with a genomic and epigenomic integrative approach . STUDY DESIGN We performed a genome-wide methylation scan using the Illumina HumanMethylation 27 BeadChip on leukocyte DNA of 11 cases of vitamin D deficiency ( serum 25-hydroxyvitamin D [ 25(OH)D ] ≤ 25 nmol/L ) and 11 age-matched controls ( [ 25(OH)D ] > 75 nmol/L ) ; the subjects were African American normal-weight ( body mass index < 85th percentile ) males aged 14 - 19 years . The Limma package was used to analyze each CpG site for differential methylation between cases and controls . To correct for multiple testing , the set of raw P values were converted to false discovery rates ( FDRs ) . We also compared our findings with the recent data from Genome-Wide Association Studies of circulating 25(OH)D levels and then performed a permutation test to examine whether the " double hit " genes were r and omly enriched . RESULTS A total of 79 CpG sites achieved raw P < .001 . Of the 79 CpG sites , 2 CpG sites survived multiple testing : cg16317961 ( raw P = 3.5 × 10(-6 ) , FDR = 0.078 , in MAPRE2 ) and cg04623955 ( raw P = 5.9 × 10(-6 ) , FDR = 0.078 , in DIO3 ) . Furthermore , 3 out of the 4 genes previously identified in the 2 Genome-Wide Association Studies were also significant at the methylation level ( DHCR7 : cg07487535 , P = .015 and cg10763288 , P = .017 ; CYP2R1 : cg25454890 , P = .040 ; CYP24A1 : cg18956481 , P = .022 ) , reflecting significant enrichment ( P = .0098 ) . CONCLUSION Severe vitamin D deficiency is associated with methylation changes in leukocyte DNA . The genomic and epigenomic approach reinforce the crucial roles played by the DHCR7 , CYP2R1 , and CYP24A1 genes in vitamin D metabolism
This meta- analysis concludes that hypovitaminosis D is associated with increased risk of hyperglycemia both in diabetic and non-diabetic subjects .
There is evidence that vitamin D status is associated with type 2 diabetes .
Many observational studies have been performed investigating the relationship of vitamin D status and circulating biomarkers of glycemic regulation .
To find out whether this association holds , we conducted a systematic review and meta- analysis of cross sectional and longitudinal studies .