Vitamin D status: Multifactorial contribution of environment, genes and other factors in healthy Australian adults across a latitude gradient
journal contribution
posted on 2023-05-17, 18:18authored byLucas, RM, Ponsonby, AL, Dear, K, Valery, PC, Bruce TaylorBruce Taylor, Ingrid van der MeiIngrid van der Mei, McMichael, AJ, Pender, MP, Chapman, C, Coulthard, A, Kilpatrick, TJ, Jim Stankovich, Williams, D, Dwyer, T
Vitamin D deficiency is common and implicated in risk of several human diseases. Evidence on the relative quantitative contribution of environmental, genetic and phenotypic factors to vitamin D status (assessed by the serum concentration of 25-hydroxyvitamin D, 25(OH)D) in free-living populations is sparse. We conducted a cross-sectional study of 494 Caucasian adults aged 18-61years, randomly selected from the Australian Electoral Roll according to groups defined by age, sex and region (spanning 27°-43°South). Data collected included personal characteristics, sun exposure behaviour, biomarkers of skin type and past sun exposure, serum 25(OH)D concentration and candidate single nucleotide polymorphisms. Ambient ultraviolet radiation (UVR) levels in the month six weeks before blood sampling best predicted vitamin D status. Serum 25(OH)D concentration increased by 10nmol/L as reported time in the sun doubled. Overall, 54% of the variation in serum 25(OH)D concentration could be accounted for: 36% of the variation was explained by sun exposure-related factors; 14% by genetic factors (including epistasis) and 3.5% by direct measures of skin phenotype. Novel findings from this study are demonstration of gene epistasis, and quantification of the relative contribution of a wide range of environmental, constitutional and genetic factors to vitamin D status. Ambient UVR levels and time in the sun were of prime importance but it is nonetheless important to include the contribution of genetic factors when considering sun exposure effects. This article is part of a Special Issue entitled 'Vitamin D Workshop'.
Funding
National Multiple Sclerosis Society
History
Publication title
Journal of Steroid Biochemistry and Molecular Biology
Volume
136
Issue
13
Pagination
300-308
ISSN
0960-0760
Department/School
Menzies Institute for Medical Research
Publisher
Pergamon-Elsevier Science Ltd
Place of publication
The Boulevard, Langford Lane, Kidlington, Oxford, England, Ox5 1Gb