As gene-editing technologies continue to improve, the field of cross-species organ transplants, or xenotransplantation, continues to grow. Shlomo Brody examines the approach of Jewish law toward the use of such technologies, particularly regarding the permissibility of implanting pig organs in humans.

Last month, doctors in Maryland completed the world’s first heart transplant using a heart that came from a genetically modified pig. This was a breakthrough because the donor pig had undergone gene editing to remove a specific type of sugar from its cells thought to be responsible for previous organ rejections in patients.

Pigs have been utilized [in such experiments] for a number of reasons: they are easy to breed and maintain (albeit with some environmental costs); they are available in wide numbers; they can be bred under pathogen-free conditions; and, most importantly, they are similar in anatomy and physiology to humans.

In the Bible, the pig is singled out because it has split hooves but does not chew its cud, thereby disqualifying it from being kosher food. “And the swine—although it has true hoofs, with the hoofs cleft through, it does not chew the cud: it is impure for you. You shall not eat of their flesh or touch their carcasses; they are impure for you” (Leviticus 11:7-8). Beyond the prohibition of eating pork, the sages also decreed that it is prohibited to raise pigs in Israel or around the world. Yet despite the prohibition of consuming pork as well as the general taboo around pigs, there was never a ritual prohibition against gaining benefit from pigs.

In 2001, in the immediate wake of al-Qaeda’s attacks on America, Jonathan Rosen was asked to write something about anti-Semitism. So many of the points he raised in the resulting essay, reproduced in full at the link below, ring true today, and make clear just how predictable so much of the global reaction to October 7 has been. Rosen reflects on what he wrote then from the standpoint of 2024:

It is worth remembering that the Nazis saw the Holocaust as self-defense, though Jews were a minuscule fragment of a giant militarized nation. This was irrational, of course, even as they spoke the language of science, redefining Jews as a biological menace, like a virus, making the murder of babies and the elderly necessary, too, because like a microbe only extermination was the cure. It was the existence of Jews that made them a provocation, just as the existence of Israel, in any borders, inspired the Hamas massacre, as its 1988 covenant, never revoked, makes abundantly clear. The towers were a similar provocation.

It was back in 2001 that Rosen found himself “awakened to anti-Semitism,” as he wrote at the time:

I am not being chased down alleyways and called a Christ-killer. . . . But in recent weeks I have been reminded, in ways too plentiful to ignore, about the role Jews play in the fantasy life of the world. Jews were not the cause of World War II, but they were at the metaphysical center of that conflict nonetheless, since the Holocaust was part of Hitler’s agenda and a key motivation of his campaign. Jews are not the cause of World War III, if that’s what we are facing, but they have been placed at the center of it in mysterious and disturbing ways.

I felt this in a different form reading coverage of Israel in European papers. Though public expressions of anti-Semitism are taboo in a post-Holocaust world, many Europeans, in writing about Israel, have felt free to conjure images of determined child killers and mass murderers. Earlier this year, the Spanish daily La Vanguardia published a cartoon depicting a large building labeled “Museum of the Jewish Holocaust” and behind it a building under construction labeled “Future Museum of the Palestinian Holocaust.”