The heterozygous, homozygous variants and the combination of the two (AG, GG, and AG + GG) were associated with a decreased risk of MPN (OR = 0.3; 95% CI = 0.21–0.43; p < 0.001, OR = 0.19; 95% CI = 0.11–0.33; p < 0.00, and OR = 0.26; 95% CI = 0.19–0.37; p < 0.001) (XPF 11985A>G SNP). The gene discussed is ERCC4; the disease is myeloproliferative disorder.