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Stem cells, cloning, and halacha
Growing new cells to replace damaged tissues or organs, cloning lifesaving organs, and miracle cures for debilitating diseases are closer than we think.
GILLIAN KLAWANSKY
While stem cell research and cloning are vastly different technologies, they are both likely to change the face of medicine.
As this reality dawns, Jewish people are faced with how we deal with this from a halachic or Jewish perspective. Halachic specialist and medical doctor, Rabbi Professor Avraham Steinberg, who was in South Africa from Israel recently, gave guidance on these cutting-edge, but ethically challenging technologies.
Stem cells are the cells within a foetus which divide and become the 200 cell types that make up the human body, says Steinberg. Once stem cells are differentiated, they’re clearly defined for their task. For example, a cell from the eye placed into the ear won’t hear because it’s already an eye cell. But before stem cells are defined, each of them can differentiate into any one of the cell types throughout the body, he says.
While there are a small number of such basic stem cells in our adult bodies, it’s difficult to isolate them, and most of them are infected by the environment, says the rabbi. “The stem cells we’re using in research therefore come from fertilised eggs where original, clean stem cells exist.” These cells can be accessed through the in-vitro fertilisation (IVF) process. “Through IVF, we get up to 20 eggs from a woman at once. We take them all out and insert the sperm, creating fertilised eggs.”
These fertilised eggs begin to divide into more cells. About five days after conception, a little ball that’s as big as a full stop forms the blastocyst. This has an outer layer, which will become the placenta if it’s implanted into a woman’s womb. Beneath this layer is a ball of 30 to 50 stem cells.
“If implanted into a womb, they’ll start to differentiate and slowly the foetus will grow into a human being,” says Steinberg. “Yet, no woman will use all 20 eggs, so there’s always an excess of fertilised eggs that she’ll never want. In Israel alone there are currently half a million fertilised eggs in a freezer that no-one claims.”
To do stem cell research, the fertilised egg must be destroyed. “We have to open the outer layer to extract the 50 stem cells,” says Steinberg. “If we know the code to tell one cell to become a brain cell, a heart cell, a liver cell, and so on, then we can cure so many illnesses prevalent in society. A further step would be to programme a cell to become an entire organ like a liver or a heart.”
Stem cell research is particularly exciting when it comes to potentially curing degenerative diseases, like Alzheimer’s, Parkinson’s, diabetes, and those underlying heart attacks and strokes. Largely associated with age, these diseases have become more prevalent over the past century as the average life expectancy has tripled.
While some tissues in the body can regenerate, like the skin which grows again after sunburn and peeling, such regenerative processes don’t exist in the brain, the heart, and in many other important areas of the body.
While stem cell research’s positive potential is incalculable, the ethical and religious implications are significant. “Is it ok to kill a fertilised egg that can potentially become a human being [in order] to extract the stem cells and use them for other purposes?” asks Steinberg.
“The Catholics say you’re not allowed to. They believe that at the moment of conception, a full human being is formed. Just like you can’t kill a living person to take his heart to save someone else, you can’t kill this ‘human being’,” he says.
“Yet, Judaism believes that this fertilised egg, that isn’t and will never be in a womb, has no potential to become a human being. Therefore, halachically, it’s not a human being. So, if we can do something good for human beings through stem cells, we should.”
Religious tension has impeded progress in stem cell research, mainly because of the massive funding it requires – funding only countries can afford. There have been various debates within the United States and the European Union because of ethical concerns surrounding the technology.
“Israel has been at the forefront of stem cell research and acquiring funding because we have good scientists and it doesn’t go against our beliefs,” said Steinberg.
Today, stem cell research is progressing, and stem cell therapy – albeit small scale – is already taking place.
Cloning poses even greater ethical concerns. We know it’s possible because of Dolly the sheep, the first mammal to be cloned from an adult cell. Yet currently, no country can clone humans because of a host of ethical concerns, said Steinberg. “Dolly was created after over 300 failed creations that had to be sacrificed. There’s no ethical justification to create 300 human beings that we’ll have to kill because they’re suffering terribly, just to get one human being that will look normal.”
Cloning doesn’t involve a pure sperm and egg. Rather, it comes from taking a mature cell – for example, a skin cell – and bringing it to embryonic stage. “Then you can implant it in an egg, place it in a womb, and it will grow and become another human. Dolly looked like a baby, but she was born at the age of the sheep from whom she was cloned, and had all its diseases.”
We can, however, conduct therapeutic cloning, cloning a new organ, not an entire human being. “I can clone my own heart from my own skin cell,” says Steinberg, “and then there’s no problem of rejection.
“Currently, someone who receives an organ donation must take lifelong anti-rejection medication because we fight any foreign entities entering our bodies.
“Most countries won’t allow therapeutic cloning for fear that it will slip into reproductive cloning. Theoretically, if we could contain it and use it only for this purpose, that might be halachically permissible. Yet because there are problems, we don’t want to do it.”
- Steinberg was invited to South Africa by the Malka Ella Fertility Fund. He’s the director of the medical ethics unit and senior paediatric neurologist at the Shaare Zedek Medical Center in Jerusalem.