Sperm have been made in the laboratory and used to father healthy baby mice in a pioneering move that could lead to infertility treatments. The Chinese research took a stem cell, converted it into primitive sperm and fertilised an egg to produce healthy pups.

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Sperm have been made in the laboratory and used to father healthy baby mice in a pioneering move that could lead to infertility treatments. The Chinese research took a stem cell, converted it into primitive sperm and fertilised an egg to produce healthy pups.