Is it permissible for my husband to implant a living cell that produces sperm into his fibrotic testicle, and does religion approve of implanting this cell if it is taken from his brother?

It is impermissible to transplant reproductive organs such as the testicles or ovaries, due to the resulting confusion of lineage, as the testicle transfers the genetic characteristics of the donor to the offspring of the recipient. This ruling extends to the transplantation of a single cell from one man's testicle into another's. Patience and supplication are advised.