Human genetic modification is the direct manipulation of the genome using molecular engineering techniques. Recently developed techniques for modifying genes are often called “gene editing.” Genetic modification can be applied in two very different ways: “somatic genetic modification” and “germline genetic modification.”
Somatic genetic modification adds, cuts, or changes the genes in some of the cells of an existing person, typically to alleviate a medical condition. These gene therapy techniques are approaching clinical practice, but only for a few conditions, and at a very high cost.
Germline genetic modification would change the genes in eggs, sperm, or early embryos. Often referred to as “inheritable genetic modification” or “gene editing for reproduction,” these alterations would appear in every cell of the person who developed from that gamete or embryo, and also in all subsequent generations.
Germline modification has not been tried in humans, but it would be, by far, the most consequential type of genetic modification. If used for enhancement purposes, it could open the door to a new market-based form of eugenics. Human germline modification has been prohibited by law in more than 40 countries, and by a binding international treaty of the Council of Europe.
For more information on the politics and ethics of gene editing, check out the following resources from the Center for Genetics and Society:
- What is US Policy on Heritable Genome Editing? What’s Expected in the New Administration?
- Heritable Human Genome Editing: Political Implications and Opportunities for Leadership: A letter to the Biden-Harris Administration
- Genetic Justice: Identity and Equality in the Biotech Age
- Assessing the Global Policy Landscape for Human Germline and Heritable Genome Editing
- The “Geneva Statement” Calls for Course Correction on Heritable Genome Editing
- The Center for Genetics and Society’s Summary of Public Opinion Polls
- Gene Editing and the Future of Reproductive Justice
- Disability Justice & Gene Editing: Exploring Multiple Perspectives
- Gene Editing and Human Rights
- A Reproductive Justice Perspective on Germline Modification
- The Case Against Germline Modification: A Reproductive Justice Perspective
Also see the following report from the Hastings Center: Scientists Disagree About the Ethics and Governance of Human Germline Editing.