Pope Francis drew a bioethical line in the sand Thursday, telling a group of doctors, scientists and patients that no potential medical or scientific benefits “can justify the destruction of human embryos.”

The Pope was meeting in the Vatican with a group of persons afflicted with Huntington’s Disease, a fatal genetic disorder that causes the progressive breakdown of nerve cells in the brain, along with family members, doctors, geneticists and scientists.

After thanking the scientists who have dedicated themselves to studying and researching a treatment for Huntington’s Disease, he reminded them that research even for the highest and most noble causes is subject to ethical restrictions.

I encourage you to always pursue your efforts “by means that do not contribute to fueling that ‘throw-away culture’ that at times infiltrates even the world of scientific research,” Francis said.

“Some lines of research, in fact, utilize human embryos, inevitably causing their destruction,” he said. “But we know that no objective, no matter how noble—such as predicted benefits for science, other human beings or society—can justify the destruction of human embryos.”

The Pope’s words have wide-ranging applications for a number of medical practices that are common today. In vitro fertilization—which the Church condemns—is such a practice, since it involves the creation of a series of extra human embryos beyond those to be implanted in a woman’s uterus, which are therefore slated for destruction.

As Saint John Paul II wrote in 1995, the creation of such “spare embryos” that are later destroyed or used for research “in fact reduces human life to the level of simple ‘biological material’ to be freely disposed of,” which is morally repugnant.

“Nothing and no one can in any way permit the killing of an innocent human being, whether a fetus or an embryo, an infant or an adult, an old person, or one suffering from an incurable disease, or a person who is dying,” he wrote.

Pope Francis’ reflections Thursday also touch on debates regarding the use of human embryos for research on cures for Parkinson’s Disease, Type 1 diabetes mellitus, Multiple Sclerosis, Lou Gehrig’s Disease, Muscular Dystrophy and many other pathologies.

The basic principle that certain human individuals should not be sacrificed for others, since their lives too are inviolable, is a core tenet of Catholic morality. According to this principle, no human life is expendable.

Current debates in the United States and elsewhere surrounding the morality of abortion inevitably return to the moral status of the human embryo and the question of whether unborn human beings also enjoy the right to life guaranteed to all persons by the 14th Amendment.

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