Furthermore, a recent study showed that guanine-thymine (GTn) microsatellite in the Hmox1 promoter decrease HO-1 expression and there was an association between long fetal and maternal GTn repeats and lower placental and serum HO-1 levels, indicating that partial loss of HO-1 activity may increase the risk of preeclampsia [22]. The gene discussed is HMOX1; the disease is preeclampsia.