Vitamin D receptor gene variants and serum vitamin D in childhood autism spectrum disorder

Objective This study aimed to examine the correlation between polymorphisms in vitamin D receptor (VDR) gene and serum vitamin D, and to determine their role in predicting childhood Autism Spectrum Disorder (ASD). Methods Children with ASD and age- and gender- matched healthy controls were recruited from the Chinese Han population. Their serum 25(OH) vitamin D was measured using competitive chemiluminescent immunoassays. The TaqMan probe approach was applied to analyze the common VDR SNPs rs731236 (Taq1), rs11568820 (Cdx2), rs1544410 (BsmI), and rs228570 (FokI). Both linear and logistic regressions were applied in data analysis. Results A total of 269 children with ASD and 320 healthy controls were recruited. Children with ASD had significantly lower levels of serum vitamin D and a significantly higher rate of vitamin D deficiency (< 20 ng/ml) compared to healthy controls (67.7% vs 34.1%). All these examined VDR SNPs were not correlated with serum vitamin D concentrations or vitamin D deficiency. Logistic regression analysis revealed that rs731236 and serum vitamin D were associated with childhood ASD. The area under the receiver operating characteristic (ROC) curve was 0.7285 for serum vitamin D. Children with both T/C genotype of rs731236 and vitamin D deficiency had a higher risk of being diagnosed with ASD. Conclusion All examined common VDR SNPs are not correlated with serum vitamin D concentrations or vitamin D deficiency. The combination of T/C phenotype of rs731236 and vitamin D deficiency are associated with a higher risk of childhood ASD. Vitamin D is a promising target in the prevention and treatment of this disease.

Automated summary

This study examined the correlation between polymorphisms in the vitamin D receptor (VDR) gene and serum vitamin D levels in children with Autism Spectrum Disorder (ASD). The results showed that children with ASD had lower levels of serum vitamin D and a higher rate of vitamin D deficiency compared to healthy controls. However, the examined VDR SNPs were not correlated with serum vitamin D levels or vitamin D deficiency. Logistic regression analysis revealed that a specific genotype and vitamin D deficiency were associated with a higher risk of childhood ASD. These findings suggest that vitamin D could be a promising target for the prevention and treatment of ASD.