Screening embryos for a wider range of genetic conditions was given the go ahead by the Human Fertilisation and Embryology Authority (HFEA), the United Kingdom's fertility watchdog, last week.

Preimplantation genetic diagnosis was already approved for a limited number of conditions with which a baby is born—such as cystic fibrosis—or that it risks developing early in life—for example, the cancers retinoblastoma and familial adenomatous polyposis. Both cancers have “high penetrance”—children born with the genetic mutation have a 90% chance of developing the condition.

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