We have recently replicated an association between low neonatal 25 hydroxyvitamin D (25OHD) and risk of schizophrenia (n = 2600, Danish case control sample). While exploring gene-environment interplay, we identified a gene-environment correlation (rGE) linking high scores on a schizophrenia-based Polygene Risk Score (PRS-Sz) with low neonatal 25 hydroxyvitamin D3 (25OHD3). This associated was present in the control sample (thus the association was not driven by the putative link between vitamin D and schizophrenia). We speculate that the PRS-Sz contains variants that are associated with 25OHD3 concentration - for example, several of the strongest GWAS hits for schizophrenia involve calcium channels, which could influence vitamin D half-life. Thus, we hypothesize that the PRS-Sz may contain (nested) sub-PRS that are related to vitamin D concentration.