By using a PRS of low folate concentrations based on 76 SNPs, as well as another PRS based on 2 SNPs within the MTHFR gene, and also the maternal rs1801133 genotype as a proxy of maternal genetic liability to folate deficiency, we included SNPs associated with different parts of folate metabolism and folate function [4,18]. The gene discussed is MTHFR; the disease is folate deficiency.