Association between polygenic risk scores and vitamin D status among Chinese healthy infants and toddlers: The role of dietary intake and supplementation practice

Hypovitaminosis D during infancy may adversely affect health and developmental outcomes in early childhood. Our study aims to explore the individual and combined effects of the eight selected genetic variants (rs4588, rs7041, rs2282679, rs2228570, rs1993116, rs4646536, rs11234027, and rs10783219) on vitamin D status among infants and toddlers with sufficient and insufficient vitamin D intake. A multi-centre cross-sectional study was conducted to recruit 616 infants and toddlers aged 7–23 months. A polygenic risk score (PRS) was computed from eight selected genetic variants. Questionnaire on family demographics, dietary intake and the use of vitamin D containing supplements were completed by parents. Participants’ vitamin D status was classified based on their serum 25(OH)D concentrations measured by Liquid Chromatography Tandem Mass Spectrometry. Analyses showed that rs7041T, rs4588A, and rs2282679C carriers had significantly lower serum 25(OH)D concentration. Participants were categorized by their PRS (Low: 1–4; Low Medium: 5–6; High Medium: 7–8; and High: 9–13), in which low risk group had significantly higher serum 25(OH)D concentration than other three groups (P<.05). Effect of PRS on vitamin D concentrations was mainly observed in participants with insufficient vitamin D intake and those not using vitamin D containing supplements (P<.05). Our study revealed the individual and combined effects of genetic variants on serum vitamin D concentrations. Sufficient vitamin D intake and the use of vitamin D containing supplements can help reduce the effect of genetic risk and should be emphasized in guidelines for the prevention of hypovitaminosis D in infants and toddlers. Copyright © 2025 Elsevier Ltd.