Don’t edit the human germ line
Abstract
The article discusses the research conducted by scientist A. Regalado and colleagues regarding the use of genome-editing tools for modification of human DNA and states that genome editing has several ethical and safety issues associated with it. It mentions that Genome-editing technologies do not affect sperms of egg, but can be used for treatment of several diseases such as HIV/AIDS, haemophilia and sickle-cell anaemia. It states that editing tools aim to eliminate disease causing mutation.
AI snapshot
Written from the paper’s full text.
TL;DR
This Nature Comment argues that genome editing of the human germ line using current technologies is dangerous and ethically unacceptable, and calls on the international scientific community to agree to a voluntary moratorium on modifying the DNA of human reproductive cells. The authors, who work on somatic-cell genome editing, warn that a public outcry over germline editing could impede promising therapeutic development in non-inheritable somatic applications.
Key findings
- Genome editing in human embryos with current technologies "could have unpredictable effects on future generations," making it "dangerous and ethically unacceptable," and could be exploited for non-therapeutic modifications.
- Technical control is limited: a nuclease may not cut both copies of a target gene, or the cell may divide before corrections complete, producing a genetic mosaic; increasing nuclease dose raises the risk of off-target cuts elsewhere in the genome.
- Quality control can currently be performed on only a subset of cells, so "the precise effects of genetic modification to an embryo may be impossible to know until after birth," and problems may not surface for years.
- Around 40 countries discourage or ban germline modification; in western Europe, 15 of 22 nations prohibit modification of the germ line, and the US NIH Recombinant DNA Advisory Committee states it "will not at present entertain proposals for germ line alterations."
Methods
- Commentary/opinion piece (Nature Comment), not an original research study; no new data are reported.
- Argument draws on cited literature on genome-editing tools (ZFNs, CRISPR/Cas9), animal embryo-editing studies in rats, cattle, sheep and pigs, and existing national/institutional policies.
- Authors disclose competing financial interests: involvement with Sangamo BioSciences and the Alliance for Regenerative Medicine, both developing somatic-cell genome-editing therapeutics.
Limitations
- As a Comment, the piece presents no primary data, systematic review or formal analysis; its claims rest on cited studies and the authors' expert judgment.
- The authors' competing interests (Sangamo BioSciences, ARM) are declared and are evident in the text as a potential source of bias toward protecting somatic-cell therapeutic development.
- The text does not quantify risks of germline editing or specify what evidence would establish safe outcomes; it states only that reproducible data over multiple generations would be needed.
Model-written summary. Check it against the paper before relying on it.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
0 of 7 cited sources checked · 0 supported · 0 flagged
- Interpretationreasoning§ Don't edit the human germ line · p. 1
Genome editing in human embryos using current technologies could have unpredictable effects on future generations.
“In our view, genome editing in human embryos using current technologies could have unpredictable effects on future generations.”
Quote in the paperSubstantial claim - Premisecitation§ LEGAL CASE · p. 2
In western Europe, 15 of 22 nations prohibit the modification of the germ line.
“This consensus is most visible in western Europe, where 15 of 22 nations prohibit the modification of the germ line 4 .”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [4] Tebas, P. et al. N. Engl. J. Med. 370, 901–910 (2014). source
Queued — the background check reaches it, usually within a day.
- Interpretationreasoning§ EDITING TOOLS · p. 2
It would be difficult to control exactly how many cells are modified when using genome editing in human embryos.
“It would be difficult to control exactly how many cells are modified.”
Quote in the paperSubstantial claim - Premisecitation§ LEGAL CASE · p. 2
Some countries discouraged or prohibited germline modification research a decade before the technical feasibility of germline modification was confirmed in rats in 2009.
“Because of such concerns - as well as for serious ethical reasons - some countries discouraged or prohibited this type of research a decade before the technical feasibility of germline modification was confirmed in rats in 2009 (ref. 9).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [9] Geurts, A. M. Science. 325, 433 (2009). source
- Interpretationreasoning§ EDITING TOOLS · p. 2
The current ability to perform quality controls on only a subset of cells means that the precise effects of genetic modification to an embryo may be impossible to know until after birth.
“The current ability to perform quality controls on only a subset of cells means that the precise effects of genetic modification to an embryo may be impossible to know until after birth.”
Quote in the paperSubstantial claim
- Interpretationreasoning§ LEGAL CASE · p. 2
The use of CRISPR/Cas9 in human embryos certainly makes onward human germline modification a possibility.
“But the use of CRISPR/Cas9 in human embryos certainly makes onward human germline modification a possibility.”
Quote in the paperSubstantial claim - Premisecitation§ LEGAL CASE · p. 2
Many countries do not have explicit legislation in place permitting or forbidding genetic engineering in humans, considering such research experimental and not therapeutic.
“Many countries do not have explicit legislation in place permitting or forbidding genetic engineering in humans - considering such research experimental and not therapeutic (see go.nature.com/uvthmu).”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites go.nature.com/uvthmu
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Interpretationreasoning§ EDITING TOOLS · p. 2
Even after birth, potential problems from genetic modification to an embryo may not surface for years.
“Even then, potential problems may not surface for years.”
Quote in the paperSubstantial claim - Interpretationreasoning§ LEGAL CASE · p. 2
If a mosaic embryo is created, the embryo's germ line may or may not carry the genetic alteration.
“If a mosaic embryo is created, the embryo's germ line may or may not carry the genetic alteration.”
Quote in the paperSubstantial claim
- Classified as probably not a substantial claim. 5
- May combine two claims. 3
Probably not a substantial claim: may not pass S4 (based).
Interpretationreasoning§ Don't edit the human germ line · p. 1A public outcry about an ethical breach in germline editing could hinder a promising area of therapeutic development, namely making genetic changes that cannot be inherited.
“We are concerned that a public outcry about such an ethical breach could hinder a promising area of therapeutic development, namely making genetic changes that cannot be inherited.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S2 (checkable), S4 (based).
Interpretationnone given§ Don't edit the human germ line · p. 1Such research could be exploited for non-therapeutic modifications.
“Such research could be exploited for non-therapeutic modifications.”
Quote in the paperNot a substantial claim- Rests on an assumption: Permitting even unambiguously therapeutic germline interventions could start a path towards non-therapeutic genetic enhancement.
Probably not a substantial claim: may not pass S2 (checkable), S4 (based).
Interpretationreasoning§ LEGAL CASE · p. 2For research involving genetic modification of the germ line, it is unclear what information would be needed-or obtainable-to adequately inform prospective parents of the risks, including to future generations.
“For research involving genetic modification of the germ line, it is unclear what information would be needed - or obtainable - to adequately inform prospective parents of the risks, including to future generations.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S2 (checkable).
Interpretationreasoning§ EDITING TOOLS · p. 2Established methods, such as standard prenatal genetic diagnostics or IVF with genetic profiling of embryos before implantation, are much better options for parents who both carry the same mutation for a disease.
“Established methods, such as standard prenatal genetic diagnostics or in vitro fertilization (IVF) with the genetic profiling of embryos before implantation, are much better options for parents who both carry the same mutation for a disease.”
Quote in the paperNot a substantial claimMay combine two claims.
Interpretationnone given§ EDITING TOOLS · p. 2Increasing the dose of nuclease used would increase the likelihood that the mutated gene will be corrected, but also raise the risk of cuts being made elsewhere in the genome.
“Increasing the dose of nuclease used would increase the likelihood that the mutated gene will be corrected, but also raise the risk of cuts being made elsewhere in the genome.”
Quote in the paperNot a substantial claimMay combine two claims.
Premisecitation§ EDITING TOOLS · p. 2Studies using gene-editing in animals such as rats, cattle, sheep and pigs indicate that it is possible to delete or disable genes in an embryo-a simpler process than actually correcting DNA sequences-in only some of the cells.
“Studies using gene-editing in animals such as rats 5 , cattle 6 , sheep 7 and pigs 8 , indicate that it is possible to delete or disable genes in an embryo - a simpler process than actually correcting DNA sequences - in only some of the cells.”
Quote in the paperSubstantial claim0 of 3 sources checkedMay combine two claims.
Interpretationreasoning§ EDITING TOOLS · p. 2In an embryo, a nuclease may not necessarily cut both copies of the target gene, or the cell may start dividing before the corrections are complete, resulting in a genetic mosaic.
“In an embryo, a nuclease may not necessarily cut both copies of the target gene, or the cell may start dividing before the corrections are complete, resulting in a genetic mosaic.”
Quote in the paperSubstantial claimProbably not a substantial claim: may not pass S3 (load-bearing).
Premisecitation§ Don't edit the human germ line · p. 1Genome-editing technologies may offer a powerful approach to treat many human diseases, including HIV/AIDS, haemophilia, sickle-cell anaemia and several forms of cancer.
“Genome-editing technologies may offer a powerful approach to treat many human diseases, including HIV/AIDS, haemophilia, sickle-cell anaemia and several forms of cancer 3 .”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [3] Carroll, D. Annu. Rev. Biochem. 83, 409–439 (2014). source
The paper relies on this without support.
All techniques currently in various stages of clinical development focus on modifying the genetic material of somatic cells, such as T cells, and are not designed to affect sperm or eggs.
“All techniques currently in various stages of clinical development focus on modifying the genetic material of somatic cells, such as T cells (a type of white blood cell). These are not designed to affect sperm or eggs.”
The paper relies on this without support.
Today, around 40 countries discourage or ban germline modification.
“(Today, around 40 countries discourage or ban it.)”
The paper relies on this without support.
Permitting even unambiguously therapeutic germline interventions could start a path towards non-therapeutic genetic enhancement.
“Many oppose germline modification on the grounds that permitting even unambiguously therapeutic interventions could start us down a path towards non-therapeutic genetic enhancement. We share these concerns.”
The paper relies on this without support.
Researchers who want to investigate the clinical uses of genetically engineered somatic cells must secure people's informed consent.
“In general, researchers who want to investigate the clinical uses of genetically engineered somatic cells must secure people's informed consent.”
The paper relies on this without support.
A voluntary moratorium in the scientific community could be an effective way to discourage human germline modification and raise public awareness of the difference between somatic and germ-cell editing.
“A voluntary moratorium in the scientific community could be an effective way to discourage human germline modification and raise public awareness of the difference between these two techniques.”
The paper relies on this without support.
In nations with policies regarding inheritable genetic modification, it has been prohibited by law or by measures having the force of law.
“However, in nations with policies regarding inheritable genetic modification, it has been prohibited by law or by measures having the force of law.”
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?
Many oppose germline modification under any circumstances, reasoning that an eventual consequence could be non-therapeutic genetic enhancement.
“Many oppose germline modification under any circumstances, reasoning that an eventual consequence could be non-therapeutic genetic enhancement.13”
From What is CRISPR/Cas9? (2016) · cites this paper as [13]
Cites
Genome editing with engineered zinc finger nucleases
Urnov, F. D., Rebar, E. J., Holmes, M. C., Zhang, H. S., & Gregory, P. D. (2010) · Nature Reviews Genetics · doi:10.1038/nrg2842 · Cited by 2,285 · see citing works
Self-citationGene Editing of <i>CCR5</i> in Autologous CD4 T Cells of Persons Infected with HIV
Tebas, P., Stein, D., Tang, W. W., Frank, I., Wang, S. Q., Lee, G., Spratt, S. K., Surosky, R. T., Giedlin, M. A., Nichol, G., et al. (2014) · New England Journal of Medicine · doi:10.1056/nejmoa1300662 · Cited by 1,357 · see citing works
Knockout Rats via Embryo Microinjection of Zinc-Finger Nucleases
Geurts, A. M., Cost, G. J., Freyvert, Y., Zeitler, B., Miller, J. C., Choi, V. M., Jenkins, S. S., Wood, A., Cui, X., Meng, X., et al. (2009) · Science · doi:10.1126/science.1172447 · Cited by 817 · see citing works
Self-citationGenome Engineering with Targetable Nucleases
Carroll, D. (2014) · Annual Review of Biochemistry · doi:10.1146/annurev-biochem-060713-035418 · Cited by 498 · see citing works
Yoshimi, K., Kaneko, T., Voigt, B., & Mashimo, T. (2014) · Nature Communications · doi:10.1038/ncomms5240 · Cited by 163 · see citing works
One-step generation of myostatin gene knockout sheep via the CRISPR/Cas9 system
(2014) · Frontiers of Agricultural Science and Engineering · doi:10.15302/j-fase-2014007 · Cited by 72 · see citing works
CRISPR/Cas9 Nuclease-Mediated Gene Knock-In in Bovine-Induced Pluripotent Cells
Heo, Y. T., Quan, X., Xu, Y. N., Baek, S., Choi, H., Kim, N.-H., & Kim, J. (2015) · Stem Cells and Development · doi:10.1089/scd.2014.0278 · Cited by 65 · see citing works
Flagged first, then by citations
Research works printed but not linked: 2
- Regalado, A. MIT Tech. Rev. http://go.nature.com/2n2nfl (2015).
- Kang, Q. et al. in Proc. 10th World Congr. Genet. Appl. Livestock Prod. http://go.nature.com/6mtz2d (2014).
Cited by
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Overcoming cellular barriers for RNA therapeutics
Dowdy, S. F. (2017) · Nature Biotechnology · doi:10.1038/nbt.3802 · Cited by 1,139 · see citing works
Gene therapy clinical trials worldwide to 2017: An update
Ginn, S. L., Amaya, A. K., Alexander, I. E., Edelstein, M., & Abedi, M. R. (2018) · The Journal of Gene Medicine · doi:10.1002/jgm.3015 · Cited by 903 · see citing works
Denning, C., Borgdorff, V., Crutchley, J., Firth, K. S. A., George, V., Kalra, S., Kondrashov, A., Hoang, M. D., Mosqueira, D., Patel, A., et al. (2016) · Biochimica et Biophysica Acta (BBA) - Molecular Cell Research · doi:10.1016/j.bbamcr.2015.10.014 · Cited by 293 · see citing works
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CRISPR–Cas9: A History of Its Discovery and Ethical Considerations of Its Use in Genome Editing
Gostimskaya, I. (2022) · Biochemistry (Moscow) · doi:10.1134/s0006297922080090 · Cited by 224 · see citing works
The Ethics of Germline Gene Editing
Gyngell, C., Douglas, T., & Savulescu, J. (2017) · Journal of Applied Philosophy · doi:10.1111/japp.12249 · Cited by 174 · see citing works
Human Germline and Heritable Genome Editing: The Global Policy Landscape
Baylis, F., Darnovsky, M., Hasson, K., & Krahn, T. M. (2020) · The CRISPR Journal · doi:10.1089/crispr.2020.0082 · Cited by 155 · see citing works
“3,28,29 The BioPolicyWiki compilation had significant limitations and flaws.”
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Editing policy to fit the genome?
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Embryo editing sparks epic debate
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Initial heritable genome editing: mapping a responsible pathway from basic research to the clinic
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- Authors
- Lanphier, E., Urnov, F., Haecker, S. E., Werner, M., & Smolenski, J.
- Affiliations
- Sangamo BioSciences (United States) (US)
- The Graduate Center, CUNY (US)
- Corresponding author
- Lanphier, Edward
- Venue
- Nature
- Published
- 2015-03-12
- Volume
- 519
- Issue
- 7544
- Pages
- 410-411
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W1992321244
- Semantic Scholar
- 0e8b3761f11683efffd045c211ba758ebf51ece3
- Cited by
- 530
- References
- 7
- Citations by year
- 2026: 25 · 2025: 27 · 2024: 27 · 2023: 22 · 2022: 20 · 2021: 39 · 2020: 54 · 2019: 60 · 2018: 51 · 2017: 64 · 2016: 63 · 2015: 76 · 2013: 1
- FWCI
- 29.96
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- Locations
- Nature (publishedVersion)
- PubMed (publishedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › CRISPR and Genetic Engineering
- Health Sciences › Medicine › Physiology › Biomedical Ethics and Regulation
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Virus-based gene therapy research
- Keywords
- human germline editing, heritable genetic modification, therapeutic benefits, genome editing safety
- MeSH terms
- Communication, Endonucleases, Genetic Engineering, Germ Cells, Humans, Research Personnel, Genome, Human, Zinc Fingers, Practice Guidelines as Topic, Germ-Line Mutation, Risk Assessment, Embryo Research, Patient Safety, CRISPR-Cas Systems
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