A government bioethics panel on Friday approved gene modifications of fertilized human eggs for basic research purposes, while rejecting the technology's clinical use due partly to the unknown impact on the next generation.
Studies on so-called genome editing are under way to use it for animals, plants and human body cells, but whether the technology should be applicable to fertilized human eggs is being debated worldwide after Chinese scientists reported gene editing of human embryos last year, in what was believed to be the world's first such case.
The government panel concluded that researchers can use modified fertilized human eggs to find out which genes play an important role in the early phase of growth, to develop treatment for congenital diseases and to improve technologies linked to reproduction.
But it added there is a need to consider whether the studies are impossible to conduct without using such fertilized human eggs.
Ethical problems also remain when gene editing is used for nonmedical treatment, such as those involving eye color or strengthening muscles, the panel said.
The panel said it cannot approve the clinical use of modified fertilized human eggs, citing risks of editing errors and the currently unknown impact on offspring. Correcting genetic defects and putting the egg back into a mother's womb is considered to be among the cases of clinical use.