CRISPR/Cas gene editing in the human germline.
Level 5 - mechanism / opinion, no new human data
Narrative review of bench and preclinical research without systematic methodology or primary human clinical trial data.
PubMed 35305903 · doi:10.1016/j.semcdb.2022.03.012
What was done
This narrative review summarizes the state of the art of CRISPR/Cas human germline gene editing (HGGE) in oocytes and embryos. It reviews methods for knocking out genes to study embryonic development, approaches to correct disease-causing mutations, technical parameters affecting editing efficacy, and the use of stem cell models as alternatives to scarce human germline material.
What was found
The abstract provides no quantitative data or numerical outcomes. It reports qualitatively that HGGE success depends on experimental variables and identifies major unresolved barriers to clinical application, specifically loss-of-heterozygosity and mosaicism.
Why it matters
This paper consolidates current knowledge on the biological and technical obstacles that prevent CRISPR-mediated germline editing from being safely used in reproductive or clinical medicine.
Limits
The abstract contains no empirical data, sample sizes, or systematic review protocol. Findings are limited by the scarcity of human oocytes and embryos, heavy reliance on non-embryo proxy models, and substantial ethical constraints governing germline modification.
Cited by
- context If a genetic edit is performed on an embryo, every developing cell in that embryo will carry the edit, including the germline cells (sperm and egg).