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RNASEH2B

ribonuclease H2 subunit B

The RNASEH2B gene provides instructions for a key component of the RNase H2 complex, an enzyme vital for breaking down RNA-DNA hybrids and maintaining genomic stability. RNASEH2B encodes the ribonuclease H2 subunit B, which is integral to the RNase H2 complex.

Chromosome 13q14.3 Various HGNC:25671 Tier C
RNASEH2B 13q14.3 p arm q arm 13

RNASEH2B is located on the long (q) arm of chromosome 13, at band 13q14.3. Arm ratio per GRCh38 - banding schematic.

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Clinical tests that include this

Carrier Screening panel
RNASEH2B is 1 of 1,008 genes on this panel
Expanded carrier screening for recessive and X-linked conditions

Overview

The RNASEH2B gene, full name ribonuclease H2 subunit B, is an important genetic component responsible for producing one part of the RNase H2 protein complex. This complex is a type of ribonuclease, an enzyme that specifically targets and breaks down molecules containing RNA. Its functions are critical for maintaining the integrity and stability of the human genome and supporting immune responses.

What the gene does

The protein encoded by the RNASEH2B gene is a subunit of the RNase H2 complex. This complex acts as a ribonuclease, primarily responsible for degrading RNA-DNA hybrids. These hybrid molecules, composed of one strand of RNA and one strand of DNA, naturally form during the process of DNA replication within cells. The RNase H2 complex's ability to remove these hybrids is crucial for preventing genomic instability.

Beyond its role in processing RNA-DNA hybrids, the RNase H2 complex is also believed to be involved in the broader mechanisms of DNA replication and the repair of DNA errors. Furthermore, it appears to contribute to the proper functioning of the immune system by eliminating unnecessary DNA fragments that could otherwise trigger an inappropriate immune response.

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Chromosome location

The RNASEH2B gene is located on chromosome 13, specifically at position 13q14.3. This chromosomal address indicates its precise segment on the long arm (q) of chromosome 13.

Protein structure

The RNASEH2B protein consists of 312 amino acids. While detailed domain architecture may be complex, a specific disordered region has been identified within the protein, spanning amino acids 236 to 256. This disordered segment may contribute to the protein's flexibility and its interactions with other molecules.

Key variants

Variants within the RNASEH2B gene can alter the protein's structure or function, potentially impacting the activity of the RNase H2 complex. These genetic changes can range from single nucleotide substitutions to larger deletions or insertions. The clinical impact of these variants varies, with some being benign and others associated with specific health conditions.

No pathogenic or likely-pathogenic ClinVar variants recorded yet for this gene.

Associated conditions

Genetic changes in the RNASEH2B gene have been linked to Aicardi-Goutières syndrome, a severe neurological disorder. This condition typically involves significant brain dysfunction, skin lesions, and other health issues. When the RNase H2 complex, which includes the RNASEH2B protein, is not functioning correctly due to these variants, it can lead to the characteristic symptoms observed in affected individuals.

No disease links recorded for this gene in our reference set.

UK clinical status

RNASEH2B is recognised within the NHS Genomic Medicine Service, being listed on several green R-code panels. These include panels for hereditary spastic paraplegia (both general and childhood onset), inherited white matter disorders, intellectual disability, and early-onset or syndromic epilepsy. It is also relevant for COVID-19 research, foetal anomalies, intracerebral calcification disorders, and primary immunodeficiency.

Green-listed
High evidence · clinically actionable in NHS testing
Included in NHS GMS signed-off panels
Dystonia, chorea or related movement disorder, childhood onset · R57 NHS GMS → Fetal anomalies · R21 NHS GMS → Hereditary spastic paraplegia, childhood onset · R61 NHS GMS → Leukodystrophy, adult onset · R62 NHS GMS → Likely inborn error of metabolism · R98 NHS GMS → Primary immunodeficiency or monogenic inflammatory bowel disease · R15 NHS GMS → DDG2P NHS GMS → Early onset or syndromic epilepsy NHS GMS →
NHS Genomic Medicine Service Jeen carrier screening

Sources: NHS GMS PanelApp · Genomics England PanelApp · NHS National Genomic Test Directory

Frequently asked questions

What does the RNASEH2B gene do?

The RNASEH2B gene provides instructions for making one part of the RNase H2 complex. This enzyme complex is crucial for breaking down RNA-DNA hybrids, which are formed during DNA replication, and plays a role in DNA repair and immune system regulation.

What condition is associated with RNASEH2B gene variants?

Variants in the RNASEH2B gene are primarily associated with Aicardi-Goutières syndrome. This is a severe neurodevelopmental disorder characterised by brain dysfunction, skin abnormalities, and other health concerns.

How is RNASEH2B relevant to the NHS Genomic Medicine Service?

The RNASEH2B gene is included on several NHS Genomic Medicine Service panels, indicating its clinical significance for conditions such as hereditary spastic paraplegia, inherited white matter disorders, intellectual disability, and early-onset epilepsy.

References

  1. Feng S, Cao Z. Is the role of human RNase H2 restricted to its enzyme activity? Progress in biophysics and molecular biology. 2016. PMID: 26603688
  2. Livingston JH, Crow YJ. Neurologic Phenotypes Associated with Mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR1, and IFIH1: Aicardi-Goutières Syndrome and Beyond. Neuropediatrics. 2016. PMID: 27643693
  3. Crow YJ, Chase DS, Lowenstein Schmidt J. Characterization of human disease phenotypes associated with mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR, and IFIH1. American journal of medical genetics. Part A. 2015. PMID: 25604658
  4. Cuadrado E, Michailidou I, van Bodegraven EJ. Phenotypic variation in Aicardi-Goutières syndrome explained by cell-specific IFN-stimulated gene response and cytokine release. Journal of immunology (Baltimore, Md. : 1950). 2015. PMID: 25769924
  5. Rice GI, Forte GM, Szynkiewicz M. Assessment of interferon-related biomarkers in Aicardi-Goutières syndrome associated with mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, and ADAR: a case-control study. The Lancet. Neurology. 2013. PMID: 24183309
  6. Chon H, Vassilev A, DePamphilis ML. Contributions of the two accessory subunits, RNASEH2B and RNASEH2C, to the activity and properties of the human RNase H2 complex. Nucleic acids research. 2009. PMID: 19015152
  7. Perrino FW, Harvey S, Shaban NM. RNaseH2 mutants that cause Aicardi-Goutieres syndrome are active nucleases. Journal of molecular medicine (Berlin, Germany). 2009. PMID: 19034401
  8. Rice G, Patrick T, Parmar R. Clinical and molecular phenotype of Aicardi-Goutieres syndrome. American journal of human genetics. 2007. PMID: 17846997
  9. Adam MP, Bick S, Mirzaa GM. Aicardi-Goutières Syndrome. 1993. PMID: 20301648
Educational content. This page is not medical or genetic advice, is not individually reviewed by a clinician for each reader, and should not replace a consultation with a qualified healthcare professional or genetic counsellor. If you are considering genetic testing or acting on a test result, book a consultation.
Data sources Last updated 27 September 2026. Content compiled from HGNC · MedlinePlus Genetics · ClinGen · Genomics England PanelApp · NHS National Genomic Test Directory · ClinVar · UniProt · AlphaFold .