ZC4H2 is a member of the zinc finger domain-containing protein family. This family member has a C-terminal zinc finger domain that is characterized by four cysteine residues and two histidine residues, and it also includes a coiled-coil region. ZC4H2 has been detected as an autoantigen in hepatocellular carcinoma patients. It has been identified as a potential candidate for X-linked mental retardation. Recombinant human ZC4H2 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.