An international group of bioethics and scientists has allowed an increase in the 14-day study period for modified human embryos, as it may be useful for medical research. This is reported in an article published in the journal Science.
Currently, the lifespan of modified human embryos is limited to two weeks after fertilization, but experts admit longer studies. This will contribute to the understanding of early fetal development disorders, and will also help to develop new treatments for infertility, malformations and prevent unsuccessful pregnancies.
National guidelines, laws and international regulations prohibit scientists from cultivating human embryos for research after 14 days or after the primordial streak appears, when the underlying tissues of the human body begin to form and the embryo can no longer split into identical twins.
Experts have proposed several principles that allow longer research periods when a number of conditions are met. For example, scientists must assess whether an experiment is informative enough to warrant its extension. In addition, applications for experiments must be reviewed by qualified and independent committees of science and ethics.
