TY - JOUR
T1 - Reduced serum vitamin D-binding protein levels are associated with type 1 diabetes
AU - Blanton, Dustin
AU - Han, Zhao
AU - Bierschenk, Lindsey
AU - Linga-Reddy, M. V.Prasad
AU - Wang, Hongjie
AU - Clare-Salzler, Michael
AU - Haller, Michael
AU - Schatz, Desmond
AU - Myhr, Courtney
AU - She, Jin-Xiong
AU - Wasserfall, Clive
AU - Atkinson, Mark
PY - 2011/10
Y1 - 2011/10
N2 - OBJECTIVE - Previous studies have noted a specific association between type 1 diabetes and insufficient levels of vitamin D, as well as polymorphisms within genes related to vitamin D pathways. Here, we examined whether serum levels or genotypes of the vitamin D-binding protein (VDBP), a molecule key to the biologic actions of vitamin D, specifically associate with the disorder. RESEARCH DESIGN AND METHODS - A retrospective, cross-sectional analysis of VDBP levels used samples from 472 individuals of similar age and sex distribution, including 153 control subjects, 203 patients with type 1 diabetes, and 116 first-degree relatives of type 1 diabetic patients. Single nucleotide polymorphism (SNP) typing for VDBP polymorphisms (SNP rs4588 and rs7041) was performed on this cohort to determine potential genetic correlations. In addition, SNP analysis of a second sample set of banked DNA samples from 1,502 type 1 diabetic patients and 1,880 control subjects also was used to determine genotype frequencies. RESULTS - Serum VDBP levels were highest in healthy control subjects (median 423.5 μg/mL [range 193.5-4,345.0; interquartile range 354.1-586]), intermediate in first-degree relatives (402.9 μg/mL [204.7-4,850.0; 329.6-492.4]), and lowest in type 1 diabetic patients (385.3 μg/mL [99.3-1,305.0; 328.3-473.0]; P = 0.003 vs. control subjects). VDBP levels did not associate with serum vitamin D levels, age, or disease duration. However, VDBP levels were, overall, lower in male subjects (374.7 μg/mL [188.9-1,602.0; 326.9-449.9]) than female subjects (433.4 μg/mL [99.3-4,850.0; 359.4-567.8]; P < 0.0001). It is noteworthy that no differences in genotype frequencies of the VDBP polymorphisms were associated with serum VDBP levels or between type 1 diabetic patients and control subjects. CONCLUSIONS - Serum VDBP levels are decreased in those with type 1 diabetes. These studies suggest that multiple components in the metabolic pathway of vitamin D may be altered in type 1 diabetes and, collectively, have the potential to influence disease pathogenesis.
AB - OBJECTIVE - Previous studies have noted a specific association between type 1 diabetes and insufficient levels of vitamin D, as well as polymorphisms within genes related to vitamin D pathways. Here, we examined whether serum levels or genotypes of the vitamin D-binding protein (VDBP), a molecule key to the biologic actions of vitamin D, specifically associate with the disorder. RESEARCH DESIGN AND METHODS - A retrospective, cross-sectional analysis of VDBP levels used samples from 472 individuals of similar age and sex distribution, including 153 control subjects, 203 patients with type 1 diabetes, and 116 first-degree relatives of type 1 diabetic patients. Single nucleotide polymorphism (SNP) typing for VDBP polymorphisms (SNP rs4588 and rs7041) was performed on this cohort to determine potential genetic correlations. In addition, SNP analysis of a second sample set of banked DNA samples from 1,502 type 1 diabetic patients and 1,880 control subjects also was used to determine genotype frequencies. RESULTS - Serum VDBP levels were highest in healthy control subjects (median 423.5 μg/mL [range 193.5-4,345.0; interquartile range 354.1-586]), intermediate in first-degree relatives (402.9 μg/mL [204.7-4,850.0; 329.6-492.4]), and lowest in type 1 diabetic patients (385.3 μg/mL [99.3-1,305.0; 328.3-473.0]; P = 0.003 vs. control subjects). VDBP levels did not associate with serum vitamin D levels, age, or disease duration. However, VDBP levels were, overall, lower in male subjects (374.7 μg/mL [188.9-1,602.0; 326.9-449.9]) than female subjects (433.4 μg/mL [99.3-4,850.0; 359.4-567.8]; P < 0.0001). It is noteworthy that no differences in genotype frequencies of the VDBP polymorphisms were associated with serum VDBP levels or between type 1 diabetic patients and control subjects. CONCLUSIONS - Serum VDBP levels are decreased in those with type 1 diabetes. These studies suggest that multiple components in the metabolic pathway of vitamin D may be altered in type 1 diabetes and, collectively, have the potential to influence disease pathogenesis.
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U2 - 10.2337/db11-0576
DO - 10.2337/db11-0576
M3 - Article
C2 - 21844098
AN - SCOPUS:80053421975
SN - 0012-1797
VL - 60
SP - 2566
EP - 2570
JO - Diabetes
JF - Diabetes
IS - 10
ER -