# Jin Billy Li
Jin Billy Li is a molecular geneticist at Stanford University whose laboratory develops and applies methods for detecting A-to-I RNA editing, the conversion of adenosine to inosine in RNA by ADAR enzymes, and for understanding what that editing does. He is known for genome-wide surveys of [RNA editing](https://www.edgepedia.org/rna-editing) sites, the RADAR database of A-to-I editing, and work showing that RNA editing marks endogenous double-stranded RNA as "self" so the innate immune sensor MDA5 does not attack it.[1](https://profiles.stanford.edu/jin-li) • [2](https://www.michaeljfox.org/researcher/jin-billy-li-phd)
| Key fact | Detail |
|---|---|
| Field | RNA editing (A-to-I), ADAR biology, transcriptome engineering |
| Training | B.S. Tsinghua 1997; M.S. Tsinghua 1999; Ph.D. Washington University in St. Louis 2005; postdoc, Harvard Medical School |
| Laboratory | Started at Stanford in 2010; Professor, Department of Genetics (some pages list associate professor) |
| Signature work | 2009 Science genome-wide RNA editing site identification; RADAR database (2013) |
| Administrative role | Director of Graduate Studies, Stanford Genetics PhD Program, 2014 to 2022 |
| Recent work | 2025 Nature Reviews Genetics review (corresponding author); 2026 cardiovascular ADAR1 review |
## Career and training
Li earned a B.S. in Biology from [Tsinghua University](https://www.edgepedia.org/tsinghua-university) in 1997 and an M.S. in Molecular Biology in 1999, then completed a Ph.D. in Genetics at Washington University School of Medicine in St. Louis in 2005.[1](https://profiles.stanford.edu/jin-li) • [3](https://ias.hkust.edu.hk/events/rna-editing-from-biology-to-therapy) He then trained as a postdoctoral fellow in Genomics and Technology at Harvard Medical School, in the laboratory of Professor George Church, and started his own laboratory at Stanford in 2010.[1](https://profiles.stanford.edu/jin-li) • [2](https://www.michaeljfox.org/researcher/jin-billy-li-phd) At Stanford he served as Director of Graduate Studies of the Genetics PhD Program from 2014 to 2022 and has been a member of the Stanford Diabetes Research Center since 2020.[1](https://profiles.stanford.edu/jin-li) The Michael J. Fox Foundation describes him as associate professor of genetics,[2](https://www.michaeljfox.org/researcher/jin-billy-li-phd) while the HKUST Institute for Advanced Study biography and his 2025 review affiliation list him as Professor in the Department of Genetics.[3](https://ias.hkust.edu.hk/events/rna-editing-from-biology-to-therapy) • [4](https://doi.org/10.1038/s41576-025-00830-5)
## RNA editing and why detection is hard
A-to-I RNA editing is carried out by ADAR enzymes, which deaminate adenosines in double-stranded RNA; according to one study, millions of adenosines are edited in mammals.[5](https://europepmc.org/article/MED/31996844) Li's laboratory co-discovered that the major function of this editing is to label endogenous double-stranded RNAs as "self", preventing recognition by MDA5, a host innate immune dsRNA sensor. The biology is confirmed genetically: mice lacking ADAR1 editing die as embryos but live a full lifespan when MDA5 is removed, and in humans, loss-of-function mutations in ADAR1 and gain-of-function mutations in MDA5 cause rare autoimmune diseases.[1](https://profiles.stanford.edu/jin-li) • [3](https://ias.hkust.edu.hk/events/rna-editing-from-biology-to-therapy)
Detecting editing sites is hard because editing looks like a sequencing mismatch: an A in the genome read as G in RNA is exactly what a DNA SNP also produces. A 2026 review names this as the major technical challenge, addressed by filtering known SNP sites or by sequencing both DNA and RNA from the same individual.[6](https://link.springer.com/article/10.1038/s42003-026-09680-1)
## Representative work
According to Li's 2009 *Science* paper, on which he was corresponding author, an unbiased assay screened more than 36,000 computationally predicted nonrepetitive A-to-I sites using massively parallel target capture and [DNA sequencing](https://www.edgepedia.org/dna-sequencing), and detected a comprehensive set of several hundred human RNA editing sites by comparing genomic DNA with RNA from seven tissues of a single individual.[7](https://doi.org/10.1126/science.1170995) His 2012 [Nature Methods](https://www.edgepedia.org/nature-methods) paper, "Accurate identification of human Alu and non-Alu RNA editing sites" (Nature Methods 9(6):579-581), addressed editing within Alu repeats (short repetitive DNA sequences scattered throughout the human genome).[8](https://pubmed.ncbi.nlm.nih.gov/27208508/) In 2013 he published RADAR, a rigorously annotated database of A-to-I RNA editing, in Nucleic Acids Research.[9](https://pmc.ncbi.nlm.nih.gov/articles/PMC9790998/)
## RNA editing databases and detection tools
RADAR annotates A-to-I events in human, mouse, and fly and provides editing levels for 38% of stored positions; the older DARNED database has not been updated since 2013 and gives no editing levels.[10](https://doi.org/10.1093/nar/gkw767) According to the 2021 REDIportal paper, the database, which embeds RADAR positions, released over 4.5 million A-to-I events from about 44 body sites of about 120 healthy GTEx individuals, and about 16 million events detected de novo in about 7,700 GTEx RNAseq samples in 2021; a 2021 paper describes RADAR and DARNED as outdated or in dismission, leaving REDIportal as the comprehensive human resource.[10](https://doi.org/10.1093/nar/gkw767) • [11](https://doi.org/10.1093/nar/gkaa916) REDIportal V3.0 currently lists 15,680,833 sites from GTEx and TCGA samples plus 107,095 non-human sites.[12](https://rediportal.cloud.ba.infn.it/atlas/index.html)
Detection pipelines are compared independently of Li's work. According to *Current Protocols*, REDItools, the first software package devoted to RNA editing profiling in RNA-seq data, predicts sites de novo without prior knowledge of the editing process.[5](https://europepmc.org/article/MED/31996844) • [13](https://journal.embnet.org/index.php/embnetjournal/article/viewFile/640/905) A 2024 benchmark recommends STAR with REDItools2 when analysis time is not a constraint, and SPRINT with BWA for the most confident identification, since SPRINT showed the highest support in REDIportal and minimized false inclusions.[14](https://www.mdpi.com/2673-6284/12/3/56)
## Recent developments
Li was corresponding author of a review on leveraging genetics to understand ADAR1-mediated RNA editing in health and disease, published in Nature Reviews Genetics on 14 April 2025.[4](https://doi.org/10.1038/s41576-025-00830-5) In 2026 he co-authored a review in [Arteriosclerosis, Thrombosis, and Vascular Biology](https://www.edgepedia.org/arteriosclerosis-thrombosis-and-vascular-biology) on ADAR1 A-to-I editing controlling RNA sensing in cardiovascular disease.[1](https://profiles.stanford.edu/jin-li) The Stanford Diabetes Research Center reports that he received a 2021 P&F award to apply his approaches to mouse and human pancreatic islets and study RNA editing in islet cell autoimmunity in type 1 diabetes, a direction he had not pursued before that award.[15](https://sdrc.stanford.edu/billy-li)
## References
1. [Jin Billy Li's Profile | Stanford Profiles](https://profiles.stanford.edu/jin-li)
2. [Jin Billy Li, PhD | Michael J. Fox Foundation](https://www.michaeljfox.org/researcher/jin-billy-li-phd)
3. [RNA Editing: From Biology to Therapy - HKUST IAS](https://ias.hkust.edu.hk/events/rna-editing-from-biology-to-therapy)
4. [Leveraging genetics to understand ADAR1-mediated RNA editing in health and disease (Nature Reviews Genetics)](https://doi.org/10.1038/s41576-025-00830-5)
5. [Investigating RNA editing in deep transcriptome datasets with REDItools and REDIportal (Current Protocols)](https://europepmc.org/article/MED/31996844)
6. [RNA editing in cardiovascular health and disease (Communications Biology)](https://link.springer.com/article/10.1038/s42003-026-09680-1)
7. [Genome-Wide Identification of Human RNA Editing Sites by Parallel DNA Capturing and Sequencing (Science, 2009)](https://doi.org/10.1126/science.1170995)
8. [Accurate identification of human Alu and non-Alu RNA editing sites (PubMed)](https://pubmed.ncbi.nlm.nih.gov/27208508/)
9. [RADAR: a rigorously annotated database of A-to-I RNA editing (PubMed Central)](https://pmc.ncbi.nlm.nih.gov/articles/PMC9790998/)
10. [REDIportal: a comprehensive database of A-to-I RNA editing events in humans (Nucleic Acids Research)](https://doi.org/10.1093/nar/gkw767)
11. [REDIportal: millions of novel A-to-I RNA editing events from thousands of RNAseq experiments (Nucleic Acids Research, 2021)](https://doi.org/10.1093/nar/gkaa916)
12. [REDIportal V3.0](https://rediportal.cloud.ba.infn.it/atlas/index.html)
13. [REDITOOLS: efficient RNA editing detection by RNA-SEQ data (EMBnet.journal)](https://journal.embnet.org/index.php/embnetjournal/article/viewFile/640/905)
14. [Benchmarking RNA Editing Detection Tools (MDPI)](https://www.mdpi.com/2673-6284/12/3/56)
15. [Jin Billy Li - Stanford Diabetes Research Center](https://sdrc.stanford.edu/billy-li)
---
*Topic: Encyclopedia › Life and health › Life and health scientists › Life scientists › Researchers in genetics, genomics, and genome engineering › Functional genomics and gene regulation*
*Initially written Sep 21, 2026 · Reviewed: Sep 25, 2026 · Edited: Sep 25, 2026; Oct 11, 2026; Oct 15, 2026 · Last review: Sep 25, 2026*
*Copyright 2026 EdgeChat AI, a subsidiary of Biostate AI.*
License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license