According to latest news flash scientists have found mice testicles can yield embryonic stem cell like cells.

A team in Germany has successfully grown mouse ESC-like cells from spermatagonial stem cells which normally turn into sperm. The ESC-like cells can be grown into all tissues of the mouse body, suggesting that if the same could be done in men, it would provide patients with a source of tissue-matched cells for repairing any damaged organs or tissue.

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May I suggest that we reserve such "ethical" testicular stem cells harvested from male mice for the so-called ethicists only?

Jokes aside if this breakthrough proves successful in humans (which I somehow doubt) it will provide yet another benefit of being a man - providing stem cell harvest for all.