@article{22813,
  author = {Dwyer T and Sun Cong and Pezic Angela and Kemp Andrew and Ellis Justine and Cameron Fergus and Ponsonby Anne-Louise and Bima Abdulhadi and Rodda Christine and van der Mei Ingrid and Chiaroni-Clarke Rachel and Qu Jun and Carlin John},
  title = {Environmental and genetic determinants of two vitamin D metabolites in healthy Australian children.},
  abstract = {<p>
<b>BACKGROUND: </b>Vitamin D deficiency has been associated with adverse health outcomes. We examined genetic and environmental determinants of serum 25(OH)D3 and 1,25(OH)2D3 in childhood.
</p>

<p>
<b>METHODS: </b>The study sample consisted of 322 healthy Australian children (predominantly Caucasians) who provided a venous blood sample. A parental interview was conducted and skin phototype and anthropometry measures were assessed. Concentrations of 25(OH)D3 and 1,25(OH)2D3 were measured by selective solid-phase extraction-capillary liquid chromatography-tandem mass spectrometry. These concentrations were deseasonalised where relevant to remove the effect of month of sampling.
</p>

<p>
<b>RESULTS: </b>Deseasonalised log 25(OH)D3 and 1,25(OH)2D3 concentrations were only moderately correlated (r=0.42, p&lt;0.001). The following predicted both 25(OH)D3 and 1,25(OH)2D3: UVR 6 weeks before the interview, natural skin and eye colour, height and vitamin D allelic metabolism score. The following predicted 25(OH)D3 only: lifetime sunburns and vitamin D allelic synthesis score. Overall, 43.5% and 25.6% of variation in 25(OH)D3 and 1,25(OH)2D3 could be explained. After accounting for 25(OH)D3 concentrations, higher UVR 6 weeks before the interview and vitamin D allelic metabolism score further predicted 1,25(OH)2D3 concentrations.
</p>

<p>
<b>CONCLUSIONS: </b>Environmental factors and genetic factors contributed to both vitamin D metabolite concentrations. The intriguing finding that the higher ambient UVR contributed to higher 1,25(OH)2D3 after accounting for 25(OH)D3 concentrations requires further evaluation.
</p>
},
  year = {2017},
  journal = {J Pediatr Endocrinol Metab},
  issn = {2191-0251},
  doi = {10.1515/jpem-2016-0088},
  language = {eng},
}