Gene Therapy and Genetic Engineering in Judaism

Using genetic technology for therapeutic purposes is acceptable, but many related issues have yet to be addressed.

Reprinted with permission from Biomedical Ethics and Jewish Law, published by KTAV.

The literature on gene therapy and genetic engineering in Jewish law is very sparse indeed. Two rabbinic articles with genetic engi­neering in their titles deal primarily with artificial insemination, in vitro fertilization and surrogate motherhood, and only briefly men­tion cloning. The production of hormones such as insulin and erythropoietin, and antibiotics and other therapeutic substances by genetic engineering through recombinant DNA technology, is certainly permissible in Jewish law because nature is being properly used by man for his benefit for the treatment and cure of illnesses. Gene therapy, such as the replacement of the missing enzyme in Tay-Sachs disease or the missing hormone in diabetes, or the repair of the defective gene in hemophilia or Huntington’s disease, if and when these become scientifically feasible, is also probably sanc­tioned in Jewish law because it is meant to restore health and preserve and prolong life. 

The technical medical problems of modifying the defective gene or genes in an individual sperm, ovum or zygote by gene surgery and implanting the replaced or repaired genes into the mother thereby producing a healthy child have not yet been surmounted. However, assuming such surgery can be successfully performed, gene sur­gery will probably be sanctioned by rabbinic authorities as a legiti­mate implementation of the mandate on physicians to heal the sick. Further, argues Rabbi Azriel Rosenfeld, genes are submicroscopic particles and no process invisible to the naked eye is forbidden in Jewish law. For example, laws of forbidden foods do not apply to microorganisms. In addition, a priest only declares ritually unclean that which his eyes can see.

DNAAnother argument favoring the permissibility of gene surgery or genetic manipulation is the fact that a sperm or ovum or even the fertilized zygote is not a person. Thus, gene manipulation is not considered as tampering with an existing or even potential human being, since that status in Jewish law is only bestowed upon a fetus implanted in the mother’s womb. One can also argue that any sur­gery performed on a live human being must certainly be permitted on a sperm or ovum or fertilized zygote. For example, if a surgical cure for hemophilia, Tay-Sachs disease or Huntington’s disease were possible, it would surely be permissible. Hence, it should cer­tainly be permissible to cure or prevent these diseases by gene sur­gery.

If it were possible to perform gene transplants by transplantation of genes from one person into the ovum or sperm of another, the following Jewish legal questions would arise: Are gene transplants considered to be a type of perverted sex act between the gene donor and the recipient? Would such transplants be forbidden, in particu­lar, if donor and recipient are close relatives? Would a child con­ceived from such a manipulated ovum or sperm be regarded as related to the gene donor? Can one draw parallels from rabbinic responsa dealing with ovarian transplants and conclude that since no sex act is involved in a gene transplant, the recipient is not for­bidden to marry the donor’s relative, and the child conceived and born following agene transplant is not related to the gene donor? In most organ transplants (kidney, cornea, heart, ovary) the organ becomes an integralpart of the recipient. A transplanted gene may be different in that it is incorporated into all cells of every tissue and organ in the body.

Rabbi Moshe Hershler warns against blinding ourselves to the po­tential of genetic engineering and gene therapy, which is no longer a dream or a fantasy but becoming a medical and scientific reality. Hershler raises the question of the permissibility (or lack thereof) of experimenting with gene therapy to try to save the life of a child with thalassemia or Tay-Sachs disease if the unsuccessful outcome of the experimentation would be a shortening of the child’s life. Hersh­ler is of the opinion that gene therapy and genetic engineering may be prohibited because “he who changes the [Divine] arrangement of creation is lacking faith [in the Creator],” and he cites as support for his view the prohibition against mating diverse kinds of animals, sowing together diverse kinds of seeds, and wearing garments made of wool and linen (Leviticus 19:19).

This line of reasoning is rejected by Rabbis Shlomo Zalman Auerbach and Yehoshua J. Neuwirth since genetic engineering is not comparable to the grafting of di­verse types of animals or seed. The main purposes of gene therapy are to cure disease, restore health, and prolong life, all goals within the physician’s Divine license to heal. Gene grafting is no different than an “organ graft.” such as a kidney or corneal transplant, which nearly all rabbis consider permissible.

Ethical and halakhic (Jewish legal) problems associated with genetic engineer­ing include speciation. Does a certain species lose its identity if other genes are introduced into it? Would the citron or etrog (Cit­rus medica Linn) used on the holiday of Sukkot for religious pur­poses lose its identity if lemon genes were introduced into it? How many transplanted lemon genes are needed to consider the etrog to be a lemon? Can the rabbinic concept of nullification (bitul) be applied to this situation?

Another example is the need for fins and scales for fish to be kosher for consumption. If genes introduced in a scaleless catfish induce scalation, does the catfish then become a kosher fish? Yet another example is the conversion by genetic engineering of annual plants into perennials. The latter are not subject to some of the laws of the Sabbatical year. Thus perennial wheat, corn or tomatoes would be permitted in Jewish law even if grown during the Sabbatical year. These problems and issues have not yet been decisively discussed and resolved by current halakhic authori­ties.

It seems clear that genetic engineering and gene therapy can and should be used to treat, cure or prevent disease. But should these techniques be allowed to alter human traits such as eye color, height, personality, intelligence and facial features? Probably not, although some rabbis including Rabbi Moshe Feinstein allow elec­tive surgery to improve one’s beauty or physical features to help in spouse selection. If tall basketball players are more successful than short ones, should we only produce tall basketball players? Obviously not. Should we create piano players with three hands? Obviously not. Should we create super microorganisms for agricul­tural purposes? Perhaps, but they may also be used for germ warfare and should, therefore, be disallowed.

To attempt to clone a human being is [according to most authorities] not legally prohibited in Judaism but is probably morally inappropriate. An example of the creation of an artificial human being or golem is cited in the Talmud (Sanhedrin 65b). The possible deleterious effects of genetic engi­neering and gene therapy are not yet fully known. Can such genetic manipulation unmask inactive cancer genes? Thus, in addition to the medical and scientific aspects of genetic engineering and DNA recombinant research, the spiritual and theological aspects also require exploration. Rabbis must examine these issues from the Jew­ish viewpoint and offer halakhic guidance to the medical and lay communities.

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