I have been asked about a case involving a patient who needed a donation of bone marrow. A young woman with the same blood type was located and she agreed to donate some of her bone marrow.
Prior to transplantation, the patientís diseased bone marrow must be inactivated. Only after such inactivation can the donated, properly functioning bone marrow be injected into the patient. After deactivating the patientís bone marrow, he would soon die without the injection of fresh bone marrow because he would be left with no bone marrow at all.
Therefore, after the young woman agreed to donate, the patientís own bone marrow was inactivated. When they went to extract some of the donorís bone marrow, they gave her an injection and she felt not well. Her parents instructed her to retract her agreement to donate and she complied with her parentsí wishes. The patient died shortly thereafter.
I was asked whether the young woman was entitled to retract her agreement to donate.
In my humble opinion it seems that even if there is no obligation to donate bone marrow to save someoneís life (just as there is no obligation to donate an organ to save someoneís life, as is stated in Pitchei Teshuva 157:15), nevertheless it is obvious that in this case it is prohibited to retract an agreement because the patientís own bone marrow was inactivated in accord with that agreement (as they informed her that they would inactivate the patientís bone marrow only on the basis of her agreement to donate. She agreed and on the basis of her agreement they inactivated the patientís bone marrow).
Her retraction and failure to donate bone marrow caused the patientís death and she is in violation of the prohibition of murder. It is therefore prohibited to retract such an agreement and she should have been compelled to donate.
(In the opinion of R. Chayyim, in his Novellae on the beginning of Yesodei ha-Torah, even passive violation of the prohibition of murder as in this case is so severe that one must allow oneself to die rather than commit the violation.)
All of this is of course so only if in the opinion of the physicians there is no threat to the life of the donor.
The young womanís claim that she had to retract her agreement because her parents instructed her to do so is clearly dealt with by Ramban and Rashba (Yevamot 6b) who wrote that there is no obligation to honour oneís parents unless they derive some benefit, as in providing them with food, drink, etc. But there is no obligation to honour a parent who instructs a son or daughter to do something from which the parent derives no benefit.
This is implied in the Tosafot (ibid. in the name of Ri) and the Maharik explicitly wrote that a son need not honour a parentís objection to his choice of spouse. This is because the parent derives no benefit in such a case. Rema (end of Y.D. 240) decided in accord with the Maharik (See my explanation in 3:275).
The daughterís refusal to donate bone marrow provides no benefit to the parents and she is therefore not obligated to honour them in this matter. All the more is she exempt from honouring her parents in our case because retracting her agreement places her in violation of the prohibition of murder and honouring oneís parents cannot permit violation of any prohibition of the Torah, as is clear in several passages in the Talmud.
As far as the obligation to donate bone marrow to save someoneís life is concerned, it seems in my humble opinion that despite the physiciansí claim that there is no present and no future danger in donating because the bone marrow remaining in the donor will reproduce and within a few months will return to its pre-donation level, nevertheless we have not yet received proof that there is no future danger. It is therefore impossible to obligate anyone to donate bone marrow (Donating blood to save someoneís life is however obligatory because the donor immediately recovers). However, although it may not be an obligation, it is certainly a great Chessed to save a Jewish life.