מחקר בתאי הגזע

שלום הרב!
קיבלתי את השאלה הזאת מתלמידה שמתחילה מסלול תואר שלישי/מחקר בארץ. היא שואלת לגבי שימוש התאי בגזע מעוברים (לאחר הפלה). אני מצרף את השאלה המקורית, באנגלית. אשמח לקבל את התייחסותו של הרב.

תודה וכל טוב!
ד. ב.

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I'm (beezrat hashem) starting a PhD next semester, but for particular programs, I have a halachik question about using embryonic stem cells in research. … So as far as my own research into the halacha goes, from what I gather, R' Tendler and the RCA say that if the source of the embryonic stem cells is a fetus created for IVF, but not used, there is no issue doing research on it. As far as if the source is from aborted tissue, the only thing I've been able to find is that it can be considered that aborted fetal tissue would be considered like a gufa and therefore assur bhanaah (this is based on the chazon ish, but it also came from googling הפלה איסור הנאה, so I definitely would want someone with more halachick authority to clarify that issue). If that's true, as a researcher, what is my halachik obligation to ensure that I only use those cells that came from IVF, and not abortion (for example, making that distinction clear to a potential boss that I ca

only use one type and not the other, and getting assignments accordingly)