The DOI matches its Crossref record; 7 of the 7 references it cites were found in a registry or an index; 4 of the 8 sources its claims cite were checked for support.
A prudent path forward for genomic engineering and germline gene modification
Open accessAbstract
A framework for open discourse on the use of CRISPR-Cas9 technology to manipulate the human genome is urgently needed , Genome engineering technology offers unparalleled potential for modifying human and nonhuman genomes. In humans, it holds the promise of curing genetic disease, while in other organisms it provides methods to reshape the biosphere for the benefit of the environment and human societies. However, with such enormous opportunities come unknown risks to human health and well-being. In January, a group of interested stakeholders met in Napa, California ( 1 ), to discuss the scientific, medical, legal, and ethical implications of these new prospects for genome biology. The goal was to initiate an informed discussion of the uses of genome engineering technology, and to identify those areas where action is essential to prepare for future developments. The meeting identified immediate steps to take toward ensuring that the application of genome engineering technology is performed safely and ethically.
Overview
AI snapshot
Written from the paper’s full text.
TL;DR
A 2015 Science policy forum from the Napa meeting argues that CRISPR-Cas9 genome engineering offers major promise but also unknown risks, especially for human germline modification. It recommends broad open discussion and, in the near term, strongly discouraging clinical human germline genome modification while research and governance proceed.
Key findings
- The Napa meeting concluded there is an urgent need for open discussion of the merits and risks of human genome modification by a broad cohort including scientists, clinicians, social scientists, the general public, and relevant public entities and interest groups.
- Near-term recommendations include strongly discouraging germline genome modification for clinical application in humans, even in lax jurisdictions; creating expert forums for education; encouraging transparent research on efficacy and specificity in human and nonhuman model systems; and convening a globally representative group to consider policies.
- The paper notes that human germline engineering methods have already been demonstrated in mice and monkeys, and it distinguishes mitochondrial transfer—which does not use CRISPR-Cas9 and was approved by the Human Fertilisation and Embryology Authority and by Parliament in the United Kingdom—from nuclear germline editing.
- No quantitative data or effect sizes are reported; the text is a consensus policy commentary.
Methods
- Design: policy forum/commentary reporting on a January 2015 Napa, California meeting of CRISPR-Cas9 developers and users and experts in genetics, law, and bioethics; all participants were from the United States.
- Data or sample: no empirical dataset; discussion focused on human germline engineering and did not address mitochondrial transfer.
- Main analysis: consensus discussion and recommendations for governance, risk assessment, public engagement, and research priorities.
Limitations
- Stated: the Napa discussion did not address mitochondrial transfer; the group was all from the United States, and the paper calls for globally representative participation.
- Stated: limits to knowledge of human genetics, gene-environment interactions, and disease pathways create uncertainty about unintended consequences of heritable germline modifications.
- Evident from the text: the recommendations are not based on systematic data or quantitative risk assessment and are advisory rather than binding.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
4 of 8 cited sources checked · 3 supported · 0 flagged · accuracy not yet measured
Every source the paper cites for this claim was checked and supports it.
In the paper
“focused on the issue of human germline engineering, as the methods have already been demonstrated in mice (6) and monkeys (7).”
§ A prudent path forward for genomic engineering and germline gene modification > MOVING FORWARD
What the sources say
- Supportedcites [6] Wang H Cell 2013 153 910 Medline 23643243 PMC3969854 source
The Introduction states that the authors use CRISPR/Cas to edit multiple genes in stem cells and mice, and the Discussion reports generating mice with multiple genetic alterations. This source supports the mice portion of the citing sentence; the monkeys portion is assigned to a separate citation. (LLM, conf=0.93)
- Supportedcites [7] Niu Y Cell 2014 156 836 Medline 24486104 source
The citation to this paper supports the monkey part of the sentence. The Summary reports CRISPR/Cas9 gene targeting in one-cell-stage cynomolgus monkey embryos and the generation of gene-modified monkeys; the mice citation is separate. (LLM, conf=0.93)
Load-bearingStrength:boosted· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Supported
The cited sources support only part of this claim — read each source’s verdict below.
In the paper
“The technique also allows DNA sequence changes in pluripotent embryonic stem cells (4) that can then be cultured to produce specific tissues, such as cardiomyocytes or neurons (5).”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
What the sources say
- Partly supportedcites [4] Mali P Science 2013 339 823 Medline 23287722 PMC3712628 sourceExperimental — accuracy not yet measured
The paper’s genome-targeting results report CRISPR-Cas9 editing in human induced pluripotent stem (iPS) cells, supporting the claim that the technique can change DNA in pluripotent cells. It does not report editing embryonic stem cells; the citing sentence attaches this source to that part, while assigning the tissue-differentiation claim to citation (5). (LLM, conf=0.88)
- Supportedcites [5] Zhu Z González F Huangfu D Methods Enzymol 2014 546 215 Medline 25398343 PMC4418970 source
Citation (4) is attached to the claim that CRISPR-Cas9 allows DNA sequence changes in pluripotent embryonic stem cells, not to the later examples of cardiomyocytes or neurons. The Introduction identifies human embryonic stem cells as human pluripotent stem cells and describes CRISPR/Cas genome editing in those cells; Section 2 reports highly efficient editing at target loci. (LLM, conf=0.93)
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Partly supported
In the paper
“Although characterized by some as another form of “germline” engineering, mitochondrial transfer raises different issues and has already been approved by the Human Fertilisation and Embryology Authority and by Parliament in the United Kingdom (10) and is being considered by the Institute of Medicine and the Food and Drug Administration in the United States (11).”
§ A prudent path forward for genomic engineering and germline gene modification > MOVING FORWARD
What the sources say
- Not matchedcites [11] U.S. Food and Drug Administration, Cellular, Tissue, and Gene Therapies Advisory Committee Meeting: Announcement www.fda.gov/AdvisoryCommittees/Calendar/ucm380042.htm; www.iom.edu/activities/research/mitoethics.aspx.
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Humans are no exception—changes to the human germ line could be made using this simple and widely available technology.”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Rests on an assumption: CRISPR-Cas9 and other genome engineering methods can be used to change DNA in the nuclei of reproductive cells (germ line).
In the paper
“For example, the CRISPR-Cas9 system enables introduction of DNA sequence changes that correct genetic defects in whole animals, such as replacing a mutated gene underlying liver-based metabolic disease in a mouse model (3).”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
What the sources say
- Not checked yetcites [3] Yin H Nat. Biotechnol 2014 32 551 Medline 24681508 PMC4157757 source
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Even this seemingly straightforward scenario raises serious concerns, including the potential for unintended consequences of heritable germline modifications,”
§ A prudent path forward for genomic engineering and germline gene modification > MOVING FORWARD
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passes- Rests on an assumption: There are limits to current knowledge of human genetics, gene-environment interactions, and disease pathways.
- Probably not a substantial claim. 2
- It may state two separate claims as one. 3
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Such studies are laying the groundwork for refined approaches that could eventually treat human disease.”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it.
In the paper
“Although characterized by some as another form of “germline” engineering, mitochondrial transfer raises different issues and has already been approved by the Human Fertilisation and Embryology Authority and by Parliament in the United Kingdom (10) and is being considered by the Institute of Medicine and the Food and Drug Administration in the United States (11).”
§ A prudent path forward for genomic engineering and germline gene modification > MOVING FORWARD
What the sources say
- Not checked yetcites [10] The Human Fertilisation and Embryology (Mitochondrial Donation) Regulations 2015 www.legislation.gov.uk/uksi/2015/572/contents/made (effective 29 October 2015).
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
In the paper
“However, this limitation has been upended by the rapid development and widespread adoption of a simple, inexpensive, and remarkably effective genome engineering method known as clustered regularly interspaced short palindromic repeats (CRISPR)–Cas9 (2).”
§ A prudent path forward for genomic engineering and germline gene modification > Abstract
What the sources say
- Not matchedcites [2] Doudna JA Charpentier E Science 2014 346 1258096 Medline 25430774
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The simplicity of the CRISPR-Cas9 system allows any researcher with knowledge of molecular biology to modify genomes, making feasible experiments that were previously difficult or impossible to conduct.”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Thus, it is now possible to carry out genome modification in fertilized animal eggs or embryos, thereby altering the genetic makeup of every differentiated cell in an organism and so ensuring that the changes will be passed on to the organism’s progeny.”
§ A prudent path forward for genomic engineering and germline gene modification > CURRENT APPLICATIONS
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes? Based: unclearIt may state two separate claims as one.
- Rests on an assumption: CRISPR-Cas9 and other genome engineering methods can be used to change DNA in the nuclei of reproductive cells (germ line).
The paper relies on this without support.
There are limits to current knowledge of human genetics, gene-environment interactions, and disease pathways.
“because there are limits to our knowledge of human genetics, gene-environment interactions, and the pathways of disease (including the interplay between one disease and other conditions or diseases in the same patient).”
The paper relies on this without support.
In the United States, human research involving heritable germline modifications currently would require an Investigational New Drug exemption from the FDA.
“In the United States, such human research currently would require an Investigational New Drug exemption from the Food and Drug Administration”
The paper relies on this without support.
In countries with a highly developed bioscience capacity, germline genome modification in humans is currently illegal or tightly regulated.
“(In countries with a highly developed bioscience capacity, germline genome modification in humans is currently illegal or tightly regulated.)”
The paper relies on this without support.
Mitochondrial transfer does not use CRISPR-Cas9.
“The Napa discussion did not address mitochondrial transfer (8, 9), a technique that does not use CRISPR-Cas9.”
The paper relies on this without support.
Public trust in science ultimately begins with and requires ongoing transparency and open discussion.
“At the dawn of the recombinant DNA era, the most important lesson learned was that public trust in science ultimately begins with and requires ongoing transparency and open discussion.”
The paper relies on this without support.
CRISPR-Cas9 and other genome engineering methods can be used to change DNA in the nuclei of reproductive cells (germ line).
“In addition to facilitating changes in differentiated somatic cells of animals and plants, CRISPR-Cas9 technology as well as other genome engineering methods can be used to change the DNA in the nuclei of reproductive cells that transmit information from one generation to the next (an organism’s “germ line”).”
The paper relies on this without support.
Off-target alterations and on-target events with unintended consequences are possible with CRISPR-Cas9.
“Considerations include the possibility of off-target alterations, as well as on-target events that have unintended consequences.”
The authors state this as an assumption.
The safety and efficacy of genome engineering technology can be ensured.
“Assuming the safety and efficacy of the technology can be ensured, a key point of discussion is whether the treatment or cure of severe diseases in humans would be a responsible use of genome engineering, and if so, under what circumstances.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“A subsequent report of the results of the conference was published in March 2015 in the journal Science [46], which essentially carried recommendations to strongly discourage work on introducing heritable changes in human embryonic cells, at least for the duration of active discussions of the social, environmental and ethical consequences of such manipulations.”
From CRISPR–Cas9: A History of Its Discovery and Ethical Considerations of Its Use in Genome Editing (2022) · cites this paper as [46]
Citations
Cites
RNA-Guided Human Genome Engineering via Cas9
Mali, P., Yang, L., Esvelt, K. M., Aach, J., Guell, M., DiCarlo, J. E., Norville, J. E., & Church, G. M. (2013) · Science · doi:10.1126/science.1232033 · Cited by 9,210
Self-citationThe new frontier of genome engineering with CRISPR-Cas9
Doudna, J. A., & Charpentier, E. (2014) · Science · doi:10.1126/science.1258096 · Cited by 7,062
Self-citationWang, H., Yang, H., Shivalila, C. S., Dawlaty, M. M., Cheng, A. W., Zhang, F., & Jaenisch, R. (2013) · Cell · doi:10.1016/j.cell.2013.04.025 · Cited by 3,495
Niu, Y., Shen, B., Cui, Y., Chen, Y., Wang, J., Wang, L., Kang, Y., Zhao, X., Si, W., Li, W., et al. (2014) · Cell · doi:10.1016/j.cell.2014.01.027 · Cited by 1,033
Genome editing with Cas9 in adult mice corrects a disease mutation and phenotype
Yin, H., Xue, W., Chen, S., Bogorad, R. L., Benedetti, E., Grompe, M., Koteliansky, V., Sharp, P. A., Jacks, T., & Anderson, D. G. (2014) · Nature Biotechnology · doi:10.1038/nbt.2884 · Cited by 951
Towards germline gene therapy of inherited mitochondrial diseases
Tachibana, M., Amato, P., Sparman, M. L., Woodward, J., Melguizo‐Sanchis, D., Ma, H., Gutiérrez, N. M., Tippner-Hedges, R., Kang, E., Lee, H.-S., et al. (2012) · Nature · doi:10.1038/nature11647 · Cited by 429
The iCRISPR Platform for Rapid Genome Editing in Human Pluripotent Stem Cells
Zhu, Z., González, F., & Huangfu, D. (2014) · Methods in Enzymology · doi:10.1016/b978-0-12-801185-0.00011-8 · Cited by 66
Flagged first, then by citations
Cited by
Sorted by citations
The CRISPR tool kit for genome editing and beyond
Adli, M. (2018) · Nature Communications · doi:10.1038/s41467-018-04252-2 · Cited by 1,545
CRISPR/Cas9 in Genome Editing and Beyond
Wang, H., Russa, M. F. L., & Qi, L. S. (2016) · Annual Review of Biochemistry · doi:10.1146/annurev-biochem-060815-014607 · Cited by 1,210
Gene therapy clinical trials worldwide to 2012 – an update
Ginn, S. L., Alexander, I. E., Edelstein, M. L., Abedi, M. R., & Wixon, J. (2013) · The Journal of Gene Medicine · doi:10.1002/jgm.2698 · Cited by 1,186
Gene therapy returns to centre stage
Naldini, L. (2015) · Nature · doi:10.1038/nature15818 · Cited by 1,184
Overcoming cellular barriers for RNA therapeutics
Dowdy, S. F. (2017) · Nature Biotechnology · doi:10.1038/nbt.3802 · Cited by 1,139
Metadata
- Authors
- Baltimore, D., Berg, P., Botchan, M., Carroll, D., Charo, R. A., Church, G., Corn, J. E., Daley, G. Q., Doudna, J. A., Fenner, M., Greely, H. T., Jinek, M., Martin, G. S., Penhoet, E., Puck, J., Sternberg, S. H., Weissman, J. S., & Yamamoto, K. R.
- Affiliations
- California Institute of Technology (US)
- Stanford Medicine (US)
- Innovative Genomics Institute (US)
- University of Utah (US)
- University of Wisconsin–Madison (US)
- Harvard University (US)
- Boston Children's Hospital (US)
- Howard Hughes Medical Institute (US)
- Stanford University (US)
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
- University of California, Berkeley (US)
- Alta Partners, One Embarcadero Center, 37th Floor, San Francisco, CA 94111, USA.
- University of California, San Francisco (US)
- Corresponding author
- Doudna, Jennifer A.
- Venue
- Science
- Published
- 2015-04-03
- Volume
- 348
- Issue
- 6230
- Pages
- 36-38
- ISSN
- 0036-8075 (ISSN-L)
- 1095-9203
- PMC
- PMC4394183
- OpenAlex
- W1987739153
- Cited by
- 733
- References
- 7
- Citations by year
- 2026: 37 · 2025: 28 · 2024: 48 · 2023: 34 · 2022: 52 · 2021: 46 · 2020: 77 · 2019: 74 · 2018: 75 · 2017: 96 · 2016: 80 · 2015: 84
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Science (publishedVersion)
- PubMed (publishedVersion)
- Zurich Open Repository and Archive (University of Zurich) (acceptedVersion)
- Europe PMC (PubMed Central) (acceptedVersion)
- PubMed Central (acceptedVersion)
- Digital Access to Scholarship at Harvard (DASH) (Harvard University) (submittedVersion, cc-by)
- CaltechAUTHORS (California Institute of Technology) (submittedVersion)
- eScholarship (California Digital Library) (submittedVersion)
- Zurich Open Repository and Archive (University of Zurich) (submittedVersion)
- Zurich Open Repository and Archive (University of Zurich)
- Funders
- Caribou Biosciences, Inc.
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › CRISPR and Genetic Engineering
- Health Sciences › Nursing › Issues, ethics and legal aspects › Biomedical Ethics and Regulation
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Ethics and bioethics in healthcare
- Keywords
- CRISPR/Cas9, germline editing, public discourse, genome editing regulation
- MeSH terms
- Biotechnology, Genetic Engineering, Germ Cells, Humans, Risk Management, Genome, Human, Genetic Predisposition to Disease, Gene Transfer, Horizontal, Genomics, Targeted Gene Repair, Clustered Regularly Interspaced Short Palindromic Repeats
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
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