H2S recovered the majority of methylation changes induced by HF in five genes including Acsl1 (100% recovered), Atg2b (100% recovered), Atp5h (99.31% recovered), Cox7a2l (100% recovered), Ndufb9 (93.18% recovered) and Ndufs4 (100% recovered). Here, NDUFS4 is linked to hydrops fetalis.