Probing the transmissibility of Alzheimer’s, our long-lost relative, re-engineering plants to fight cancer. This week in Abstract Science.

A New Risk for Alzheimer’s?

(Nature, 9/9/2015, Alison Abbott)

Autopsy studies of the brains of eight people who died of the rare but deadly Creutzfeldt-Jakob disease (CJD) (the human form or mad cow), showed that they contracted it decades after treatment with contaminated batches of growth hormone that had been extracted from the pituitary glands of human cadavers. Six of the brains, in addition to the damage caused by CJD, harbored the tell-tale amyloid pathology that is associated with Alzheimer’s disease. The findings, appearing this week in Nature, mark the first evidence of real-world transmission of amyloid pathology, says molecular neuroscientist John Hardy of University College London. If confirmed, the findings raise the spectre that tens of thousands of other people treated with the human growth-hormone (hGH) extracts might be at risk of Alzheimer’s. And although there is no suggestion that Alzheimer’s could be contracted through normal contact with patients, some scientists worry that the findings may have broader implications: that Alzheimer’s could be passed on by other routes through which CJD can be transmitted, such as blood transfusions or contaminated surgical instruments.

Meet the Relatives

(Nature, 9/10/2015, Ewen Callaway)

The headlines were filled this week about the discovery of a new species in human lineage. One particularly interesting angle is how paleoanthropologists unearthed the trove of 1,550 fossil elements. They turned to social media to find experienced excavators willing to collect the delicate remains before they deteriorated further. The post was issued by Lee Berger about two years ago not long after cavers, peering through a crack in the limestone wall of the Rising Star cave system near Johannesburg, South Africa, saw a large cache of bones. Within a month after placing the social media post, Berger had lined up a team of six scientists. Two studies describing the findings appeared this week in the open access journal eLife.

The remains belong to at least 15 individuals of a previously undescribed species that the team has dubbed Homo naledi, and they may mark the oldest known deliberate burial in human history, scientists believe. The research marks a milestone in a campaign to transform palaeoanthropology into an open and inclusive field, in which rare fossils are rapidly shared with the scientific world instead of being squirreled away as an elite few scrutinize them for years.

Re-engineering Plants to Fight Cancer

(Science, 9/10/2015, Robert Service)

Throughout history, people have relied on plants for medicines. Even modern drug makers get about half their new drugs from plants. But that’s harder to do when plants are slow growing and endangered. This week, researchers reported that they were able to engineer a common laboratory plant to produce the starting material for a potent chemotherapy drug originally harvested from an endangered Himalayan plant. The new work could ensure an abundant supply of the anticancer drug and make it easier for chemists to tweak the compound to come up with safer and more effective versions. The findings appeared this week in Science.

—Compiled by Senior Scientific Writer Regina McEnery