Methylation Biosignature in Childhood Chronic Kidney Disease

Chronic kidney disease (CKD) and end-stage renal disease are highly prevalent in Taiwan. Cardiovascular disease (CVD) is the most common cause of death in children with CKD. Nitric oxide (NO) deficiency links CKD and CVD. Asymmetric dimethylarginine (ADMA), a NO synthase inhibitor, its level is increased in kidney disease and cardiovascular disease and serves as a methylation biomarker. In addition to ADMA, uremic environment, hyperhomocysteinemia (Hcy) and oxidative stress may affect DNA methylation. S-adenosylmethionine (SAM) is an important human methyl donor. S-adenosylhomocysteine (SAH) is demethylated product. Methylenetetrahydrofolate reductase (MTHFR), a folate metabolism enzyme can regulate methylation pathway. The investigators intend to examine whether ADMA, SAM/SAH ratio, Hcy, and MTHFR gene methylation can serve as biosignature to predict CVD in children with CKD children.