ADAR Gene: Adenosine Deaminase RNA Specific
A-to-I RNA Editing Enzyme: Genetics, Function, and Disease Associations
Gene Information Card
| Symbol | ADAR |
|---|---|
| Full Name | Adenosine Deaminase RNA Specific |
| Gene Type | Protein coding |
| Chromosomal Location | 1q21.3 |
| NCBI Gene ID | 103 ncbi.nlm.nih.gov/gene/103 |
| Ensembl ID | ENSG00000160710 |
| UniProt ID | P55265 |
| OMIM ID | 146920 |
| HGNC ID | 225 |
| Aliases | ADAR1, DSH, DRADA, AGS6, G1P1, IFI-4, K88DSRBP, ADAR1p150, ADAR1p110 |
Description
The ADAR gene encodes the enzyme adenosine deaminase acting on RNA, which catalyzes the deamination of adenosine to inosine in double-stranded RNA (A-to-I editing). This editing alters RNA structure and coding potential, impacting gene expression and protein diversity. ADAR is involved in immune modulation, neuronal function, and development. Mutations in ADAR are associated with Aicardi-Goutières syndrome and dyschromatosis symmetrica hereditaria, and altered expression is linked to various cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Aicardi-Goutières syndrome 6 (AGS6) | Loss-of-function mutations reduce A-to-I editing, leading to accumulation of double-stranded RNA and activation of innate immune response (type I interferon). | OMIM; ClinVar; PMID: 22521418 |
| Dyschromatosis symmetrica hereditaria (DSH) | Mutations in ADAR cause autosomal dominant DSH, likely due to haploinsufficiency affecting RNA editing in melanocytes. | OMIM; ClinVar; PMID: 12786774 |
| Bilateral striatal necrosis / Dystonia | Biallelic ADAR mutations have been reported in patients with dystonia and striatal necrosis, suggesting a neurodevelopmental role. | ClinVar; PMID: 28112019 |
| Hepatocellular carcinoma | ADAR overexpression and altered editing of specific transcripts (e.g., AZIN1) contribute to tumor progression. | COSMIC; PMID: 23563181 |
| Chronic myeloid leukemia | ADAR1 p150 isoform is overexpressed and promotes blast crisis through editing of specific mRNAs. | COSMIC; PMID: 23352160 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | High | High expression in multiple brain regions (cerebellum, cortex, hippocampus) based on GTEx data. |
| Lung | Medium | Moderate expression in lung tissue. |
| Liver | Medium | Moderate expression in liver. |
| Kidney | Medium | Moderate expression in kidney. |
| Testis | High | High expression in testis. |
| Spleen | Medium | Moderate expression in spleen. |
| Thymus | Medium | Moderate expression in thymus. |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | High | Cervical carcinoma cell line; high ADAR expression. |
| K562 | Medium | Chronic myeloid leukemia cell line; moderate expression. |
| HepG2 | Medium | Hepatocellular carcinoma cell line; moderate expression. |
| A549 | Medium | Lung carcinoma cell line; moderate expression. |
| MCF7 | Low | Breast cancer cell line; low expression. |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.3019G>A (p.Ala1007Thr) | Missense | Rare (0.01% in gnomAD) | Reduced editing activity; associated with AGS6. |
| c.577C>T (p.Arg193Ter) | Nonsense | Rare | Loss of function; causes DSH. |
| c.1334A>G (p.Glu445Gly) | Missense | Rare | Impaired editing; reported in AGS6. |
| c.2086G>A (p.Gly696Arg) | Missense | Rare | Dominant negative effect; associated with DSH. |
| c.3547C>T (p.Arg1183Trp) | Missense | Rare | Reduced editing; linked to AGS6. |
Mutation functional classification
Loss of Function (LOF)
Loss-of-function mutations (e.g., nonsense, frameshift) reduce ADAR enzymatic activity, leading to decreased A-to-I editing. This results in accumulation of double-stranded RNA and activation of the interferon response, as seen in Aicardi-Goutières syndrome.
Gain of Function (GOF)
Gain-of-function mutations are not well-documented for ADAR. However, overexpression of ADAR (especially p150 isoform) in cancers can lead to increased editing of specific transcripts, promoting tumor progression.
Dominant Negative (DN)
Some missense mutations (e.g., p.Gly696Arg) act in a dominant-negative manner, interfering with the wild-type ADAR dimer function, leading to haploinsufficiency and DSH.
View complete mutation data：
Gene Ontology (GO)
| • Adenosine deaminase activity | • Double-stranded RNA binding |
| • RNA binding | • Zinc ion binding |
| • mRNA editing | • Response to virus |
| • Innate immune response | • Nucleus |
| • Cytoplasm |
Pathways
• A-to-I RNA editing
• Innate immune response (RIG-I/MDA5 signaling)
• Interferon signaling
Protein Summary
The ADAR protein (ADAR1) is a 1226-amino acid enzyme that catalyzes the hydrolytic deamination of adenosine to inosine in double-stranded RNA. It contains two Z-DNA binding domains (Zα and Zβ), three double-stranded RNA binding domains (dsRBDs), and a deaminase domain. Two isoforms exist: p150 (interferon-inducible, cytoplasmic) and p110 (constitutive, nuclear). ADAR1 plays critical roles in RNA editing, gene regulation, and suppression of innate immune responses. It is essential for normal hematopoiesis and neuronal function.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| ADAR Knockout HEK293 Cell Line | EDJ-KQ2377 | Human | 103 | Details Get a Quote |
| ADARB1 Knockout HEK293 Cell Line | EDJ-KQ3239 | Human | 104 | Details Get a Quote |
| ADARB2 Knockout HEK293 Cell Line | EDJ-KQ4008 | Human | 105 | Details Get a Quote |
| ADAR Knockout A-549 Cell Line | EDJ-KQ22842 | Human | 103 | Details Get a Quote |
| ADAR Knockout HCT 116 Cell Line | EDJ-KQ22843 | Human | 103 | Details Get a Quote |
| ADAR Knockout HeLa Cell Line | EDJ-KQ22844 | Human | 103 | Details Get a Quote |
| ADARB1 Knockout A-549 Cell Line | EDJ-KQ24754 | Human | 104 | Details Get a Quote |
| ADARB1 Knockout HCT 116 Cell Line | EDJ-KQ24755 | Human | 104 | Details Get a Quote |
| ADARB1 Knockout HeLa Cell Line | EDJ-KQ24756 | Human | 104 | Details Get a Quote |
| ADARB2 Knockout HeLa Cell Line | EDJ-KQ52548 | Human | 105 | Details Get a Quote |
| ADARB2 Knockout A-549 Cell Line | EDJ-KQ61031 | Human | 105 | Details Get a Quote |
| ADARB2 Knockout HCT 116 Cell Line | EDJ-KQ69506 | Human | 105 | Details Get a Quote |
Displaying Records 1 To 12 Of 12 Records
