In a technical tour de force, Japanese researchers created eggs and sperm in the laboratory. Now, scientists have to determine how to use those cells safely — and ethically.
"Biologist Katsuhiko Hayashi discovered a way to turn mouse skin cells into sperm and egg cells — and actually used these modified cells to create a living baby mouse. Cells from a male mouse could be converted into eggs. Mice that were infertile could become fertile again, by turning their skin cells into viable germ cells. However, both iPS and embryonic stem cells frequently pick up chromosomal abnormalities, genetic mutations and epigenetic irregularities during culture. 'There could be potentially far-reaching, multi-generational consequences if something went wrong in a subtle way,' says Moore." (read).