(CN) - The European Court of Justice mostly adopted an adviser's opinion in setting the legal definition of "human embryo" on Tuesday while also limiting the embryo's ability to be patented.
Greenpeace initiated the dispute by challenging a German researcher who wanted to patent a process involving stem cells to treat Parkinson's disease.
Germany's Federal Court of Justice referred the case to the Court of Justice of the European Union in Luxembourg, which acts as the EU's high justice court.
In March, an adviser to the high court said embryonic stem cells that could develop into human beings cannot be patented.
With this recommendation in mind, the high court said Tuesday it had focused on the juridical definition of "human embryo" within the existing legal framework, and not on ethical or medical questions associated with the issue.
Since the preservation of human dignity is a pre-eminent goal of EU law, the term must be understood in a broad sense to protect anything that could develop into a human being, according to the court.
This includes a fertilized human egg; an ovum with the inserted cell nucleus from another mature human (the process by which cloning would occur); and division of a human egg through parthenogenesis, an asexual form of reproduction that is still under experiment for humans.
In terms of blastocysts - the entity that exists about five days after fertilization - the adjudicating court should consider whether it could develop into a human being as it defines whether it's an embryo, the high court said.
Although the high court noted that scientific research is distinct from the commercial and industrial fields, it also pointed out that a patenting process is inherently commercial.
As such, scientific research involving human embryos cannot be patented, the court said. An exception to this could apply only in the case of treating an embryo to correct genetic defects or increase its chances of viability.
The court concluded that any invention involving the destruction of a human embryo could not be patented - even if it didn't actually involve the embryo anymore.
Finally, the ruling also distinguished human embryos from pluripotent cells, which are derived from stem cells but have only the ability to develop into skin, muscle or nerve tissue, and not into an entire human being.
While religious groups including European Catholic bishops hailed the ruling, scientists - including Oliver Brüstle, the one subject to the original challenge in Germany - have expressed disappointment.
Human ova used for scientific research are often "leftovers" from in-vitro fertility treatment.
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