The association between gestational vitamin D levels and offspring vitamin D receptor polymorphisms in...

The relationship between gestational vitamin D status and offspring autism remains inconsistent, potentially due to genetic differences in vitamin D receptor (VDR) interactions. This exploratory study examined associations between maternal serum vitamin D concentrations, offspring VDR genotypes (BsmI, Fok1, ApaI, TaqI), and autism symptomatology using the Australian Scale for Autism Spectrum Conditions (ASASC) in 192 mother-child pairs at 11-years follow-up. No association was found between gestational vitamin D levels and total ASASC scores, nor between VDR genotype and total ASASC scores. Secondary subscale analyses revealed that higher early vitamin D concentrations were associated with decreased fact-orienting scores in males (β= - 0.05, 95% CI - 0.08, - 0.01, p = 0.02). Additionally, the homozygous recessive TaqI genotype was associated with a 2.5-unit increase in fact-orienting scores compared to the homozygous dominant genotype (β = 2.52, 95% CI 0.36, 4.69, p = 0.02), no significant associations were observed for vitamin D and other ASASC subscales or total scores. Due to the large number of comparisons, no adjustments for multiple testing were made; thus, significant findings should be interpreted with caution. While overall autism traits were unrelated to gestational vitamin D or VDR genotype, preliminary results may suggest modulation of specific autism-related traits by maternal vitamin D levels and offspring genetic variation.