The RNASEH2C gene encodes a non-catalytic subunit of the RNase H2 ribonuclease complex. The other members of this complex are encoded by RNASEH2A and RNASEH2B. As a ribonuclease enzyme, this complex is involved in the cleavage of RNA from RNA-DNA hybrids formed during DNA replication. For example, the enzyme is believed to mediate the removal of RNA primers from lagging-strand Okazaki fragments during DNA replication.
By carrying out its function, the enzyme plays a role in preventing inappropriate immune system activation. Dysfunction of the gene results in the build-up of unneeded DNA and RNA in the cells. The body’s immune system mistakenly identifies this DNA and RNA as foreign antigens, thus triggering an immune response with severe pathological consequences. Mutations in the RNASEH2C gene are associated with Aicardi-Goutieres Syndrome 3, a rare encephalopathy characterized by microcephaly, delayed psychomotor development, chilblains, intracranial calcification and lymphocytosis in the cerebrospinal fluid.