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A one-of-a-kind rhesus macaque named Grady is growing up under intense scrutiny at the Oregon National Primate Research Center in Beaverton. That’s because she has an unusual pedigree: researchers created her using sperm from tissue harvested from her father’s testicles when he was young, and then grafted onto his body as an adult. If all goes well with Grady, the technique might one day be used to restore fertility in boys who have received damaging cancer treatments.