This Shabbat, my neighbor dragged me into a discussion of a particular article from Torah Tidbits, the thousand-issue behemoth that is second-to-none in telling you which Torah portion has the seventeenth-lowest total number of commandments but the seventeenth-highest number of letters per verse. This particular piece was written by Rabbi Gideon Weitzman of the PUAH (Fertility and Medicine in Accordance with Halacha) Institute. Now, PUAH does great work, helping couples navigate the treacherous waters where modern reproductive science and traditional Jewish law meet. He notes, apropos of the mitzva of circumcision mandated in the Torah portion of Bo, that the Talmud (Yevamot 64b) states that if a woman's first two boys die due to circumcision, the third must not be circumcised.
The mitzva of circumcision is a very important one: If a Jew wasn't circumcised as a baby and refuses to undergo Mila as an adult, he can be liable for the punishment of karet - being “cut off”, excluded - on a par with such sins as eating on Yom Kippur, eating chametz on Pesach, doing forbidden types of work on Shabbat, and various immoral sexual acts. Nevertheless, though in this particular Talmudic case we cannot know for sure that the third son actually has hemophilia - it is only a possibility, at most a probability - the concern for human life and the Rabbis’ comprehension of the possible risk of death override the obligation to circumcise the child.Fair enough. R. Weitzman is making the point that human life is a halakhic value of supreme importance. That's not the whiplash part. That came with R. Weitzman's continuation, where he sets out the difference of opinion in the Shulchan Arukh regarding whether this applies even if the man remarries. The Mechabber, Rav Yosef Karo (YD 263:2) rules that it does, but Rav Moshe Isserles (the Rema) is not so sure. What does this tell us?
While the above reasoning is not in keeping with our modern understanding of medicine, the discussion does reveal how the Rabbis recognized Mendelian Inheritance as being sex-linked, and passed on from generation to generation.So let's get this straight. The rabbis had a deep understanding of modern genetics? Well, hemophilia is X-linked, and since we Jews only circumcise boys, who are XY, the X must come from the mother. So one of the opinions cited by the Rema (that the hemophilia can only come from the mother) is correct and based on science, while the other one, which is the one cited by the Mechabber, is what? Anti-scientific? Non-scientific?
The Shulchan Aruch then goes further and states that if two sisters were to have sons, and both babies died as a result of circumcision, the sons of any remaining sisters in the family would be exempt from the mitzva of brit mila.
The above discussion suggests a deep understanding of the existence of familial genetic abnormalities. The Rabbis’ rulings seem to be based on medical information similar to the complex family history drawn up during a session of modern genetic counseling, today.
Of course, when the Mechabber then says that we would consider two sisters as being evidence of carrying the disease, then he does line up with science. Did he discover genetics between one line and the next?
Even more laughable is R. Weitzman's contention that the Vilna Gaon's comment ad loc. about "the blood coming from the mother" is evidence of knowing about X chromosomes. That's ludicrous; he's quoting another Talmudic statement:
The father provides the white material from which the bones and the brain in the head are formed. The mother provides the red material from which skin and flesh are made. [Nida 31a].Sorry, R. Weitzman, but turning the sages of the 6th or the 16th century into geneticists is an insult to your readers' intelligence. These great men were still men, and as human knowledge increases, the Torah must grow as well.