In our step-wise logistic regression multivariate analysis, after adjusting for the effect of all genes evaluated (including MTHFR and APOE) and factors known to influence the prevalence of XFS/XFG, including sex, diabetes, hypertension, cardiovascular disease, and vascular disease, both SNPs remained significantly associated with the risk of developing XFS and XFG. The gene discussed is MTHFR; the disease is cardiovascular disorder.