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Human eggs are the key starting point for the groundbreaking experiments underway in this lab. It's run by Shoukhrat Mitalipov, a biologist who's been on the cutting edge of embryonic genetic research for decades. Mitalipov and his international team electrified the world this summer when the group announced it had successfully — and seemingly safely — figured out how to efficiently edit the DNA in human embryos. (Stein, 8/18)

Kyle, a 29-year-old Sydneysider, never knew a time when HIV wasn’t a persistent and pernicious threat — until he began popping a pill to prevent it. The blue, oval-shaped antiviral tablet, known as Truvada, that Kyle takes daily is the subject of a study in Australia’s New South Wales state that, in less than a year, has helped drive new cases of the AIDS-causing human immunodeficiency virus among gay and bisexual men to the lowest since 1985. ...Thirty-six years after a rare lung infection in gay men in Los Angeles heralded the start of the AIDS epidemic in North America, the deadly disease is firmly in retreat globally. For the first time, more than half of all people living with HIV are on virus-suppressing treatment that staves off symptoms and prevents transmission. (Gale, 8/17)

These minty bacteria are genetically engineered relatives of Mycobacterium tuberculosis, the bacterium that kills 1.5 million people each year. Thankfully this strain — Mycobacterium smegmatis — is harmless. But it’s a close enough cousin that scientists can use it as a proxy for the real thing. And though a mint-scented bacterium might seem like a silly achievement, it’s part of a serious strategy by a team of Harvard scientists to speed up discovery of a better tuberculosis vaccine. Their goal: to modify the germ so that it can be safely given to people to test a vaccine – and if the vaccine doesn’t work, that the participants can be cured. (Wosen, 8/18)

It’s neuroscience’s oldest and most acrimonious debate. On one side, scientists who aver that blasting away toxic plaques called amyloid is the best path toward treating Alzheimer’s disease. On the other, frustrated skeptics ready to ditch the amyloid hypothesis once and for all. But a parade of failed clinical trials has seeded a growing middle ground of agnostics and stoked a bevy of new research efforts, as “the field in general — and our pharma colleagues — are recognizing that they need to think beyond amyloid,” said Dr. David Knopman, a neurologist at the Mayo Clinic. (Garde, 8/18)

Safe Start, funded by the pharmaceutical giant Merck, is a small but innovative example of efforts to reverse a disturbing trend: While deaths as a complication of pregnancy have been falling around the globe, including in many poor countries, the U.S. maternal mortality rate has doubled since the 1990s. And Philadelphia’s rate is even higher than the national average. (McCullough, 8/17)

Nicotine replacement therapy products, which have been sold over the counter at drugstores since 1996, are effective only when paired with counseling, according to a UCSF study released Thursday. Without that, relying on such products can actually make it harder to kick tobacco, the study found. (Johnson, 8/17)