Researchers edit genes in human embryos for second time

Researchers in China have edited the genes of human embryos to make cells resistant to HIV infection. It’s the second reported case of using molecular scissors called CRISPR/Cas9 to alter genes in human embryos. In the new work, published April 6 in the Journal of Assisted Reproduction and Genetics, the researchers snipped a gene called […]

Pieces of Homo naledi story continue to puzzle

ATLANTA — Homo naledi, a rock star among fossil species in the human genus, has made an encore. Its return highlighted debate over whether this hominid was a distinct Homo species that purposefully disposed of at least some of its dead. H. naledi made worldwide headlines last year when researchers announced the discovery of an […]

Evidence conflicts on iron’s role in Parkinson’s disease

Iron, says aging expert Naftali Raz, is like the Force. It can be good or bad, depending on the context. When that context is the human brain, though, scientists wrangle over whether iron is a dark force for evil or a bright source of support. Some iron is absolutely essential for the brain. On that, […]

This week in Zika: First mouse study proof that Zika causes microcephaly

In case there were any lingering doubts, three new studies published May 11 could cement the theory that Zika virus infection in utero causes birth defects. One shows that mice engineered to be susceptible to Zika can pass the virus to offspring via the placenta. In these pregnant mice, which have severely crippled immune systems, […]

Risk identified in procedure for ‘three-parent babies’

A new study sounds a cautionary note for a controversial procedure used in creating “three-parent babies.” That procedure replaces defective mitochondria, the energy-generating organelles in cells, with healthy ones. But even a tiny amount of defective mitochondria may replicate and take over the cell, researchers report online May 19 in Cell Stem Cell. Exactly which […]

Deepwater Horizon oil spill caused months-long ‘dirty blizzard’

A “dirty blizzard” bombarded the Gulf of Mexico seafloor with pollution from the 2010 Deepwater Horizon oil spill for months after workers sealed the leak, new research shows. Marine snow, an organic material that floats down from the ocean’s upper layers, carried the pollution to the seafloor, researchers report the week of May 30 in […]

Electric eels play defense with a mighty leap

There are some pets that you just don’t pet. But that didn’t stop Philip Stoddard, a zoologist at Florida International University in Miami, from petting his pet electric eel Sparky. “It was so beautiful, I had to pet it,” he told Science News for Students. That was a big mistake, writes Roberta Kwok, because Sparky […]

Juno is closing in on Jupiter

Ancient stargazers chose well when they named the solar system’s largest planet, Jupiter, after the king of the Roman gods. With more than twice the mass of all the other planets combined, Jupiter reigns supreme. It’s the most influential member of our planetary family — after the sun. Jupiter might have hurled the asteroids that […]

Cities create accidental experiments in plant, animal evolution

AUSTIN, TEXAS — Cities have become great unintentional experiments in evolution. Urban life can alter the basic biological traits of its plant and animal residents, down to the taste of leaves or the stickiness of toes, researchers reported at the 2016 Evolution conference. For white clover (Trifolium repens), leaf taste matters as a defense against […]

Artificial hearing has come a long way since 1960s

‘Hearing’ electrically — A deaf person has been able to “hear” as a result of direct electrical excitation of auditory nerve fibers. But what he can hear may not make much sense…. Although speech-modulated stimuli were not understood, they were unerringly recognized as speech, mainly by rhythm and volume cues…. Optimism about the possibility of […]