India’s DNA map uncovers millions of missing genetic variants

India’s biggest gene-sequencing effort has shed new light on the diversity of the population, identifying nearly 130 million genetic variants, almost a third of which have not been reported previously. The GenomeIndia project analysed the whole genomes of almost 10,000 people, uncovering 44 million variants that weren’t already in global scientific databases. The study also revealed genetic risk factors in some populations, such as variants in genes that affect how the body processes certain drugs, variants linked to anaesthesia-related complications and extremely high levels of genetic homozygosity — when individuals inherit identical forms of a gene at a particular chromosome location from both parents. This can be a risk factor for recessive genetic diseases.

Did Homo erectus and Denisovans mate? Tooth proteins hint at ancient trysts

Ancient proteins extracted from the teeth of Homo erectus individuals that lived in China suggest that the group might have interbred with Denisovans, another archaic human species. Researchers used enamel proteins from six H. erectus individuals and identified an amino-acid variant that’s previously been seen in Denisovans. The group also identified two amino-acid sequence variants shared by all six individuals that set H. erectus apart from humans and other human relatives — something that has proved hard to find in the past.

Ice core reveals longest-ever continuous record of Earth’s climate

A 2.8-kilometre-deep ice core has yielded the longest continuous record of Earth’s climate and atmospheric conditions, stretching back 1.2 million years. Data from the core show how the concentration of carbon dioxide in the atmosphere tracked changes in global temperatures across multiple cycles of climate change. The core covers a period in Earth’s history during which ice ages became less frequent but more brutal. Researchers are hoping the oxygen isotopes and carbon dioxide in the core can provide some hints as to what caused the switch.

Revealed: the mysterious ‘dark’ proteins that might play a big role in biology

‘Dark’ portions of the genome, which weren’t thought to hold instructions for making working proteins, have mostly been excluded from research. Now thousands of the proteins encoded by these genes have an official, new name — peptideins — that marks their inclusion in major gene and protein databases used by the life-sciences community. Dark proteins tend to be very short in amino acid length and lack evolutionary relatives in other organisms, which is part of the reason they have been omitted.

The exotic particles that could finally break the Standard Model

Physicists know that their elegant theoretical description of forces and particles — the Standard Model — must be incomplete, because there are a host of phenomena it cannot explain. But observations continue to confirm the model’s accuracy with ever greater precision. Thank goodness an analysis from an experiment at the Large Hadron Collider at CERN, Europe’s particle physics laboratory, suggests at least one way out: the decay of particles called B meson. A new analysis found that the angle at which the final products emerge from the decay disagree with those predicted by the Standard Model. Evidence for this anomaly has been growing since 2015.

Roman Empire’s collapse created a genetic melting pot in Europe

An analysis of ancient genomes from hundreds of burials in southern Germany reveal that the transition from Late Antiquity to the Early Middle Ages was more complex than the stereotype of northern ‘barbarians’ running roughshod over a Roman Empire in decline. Instead, the genomes point to gradual genetic and cultural shifts that occurred through small-scale migration and intermarriage. Shared patterns of DNA show that northern Europeans “haven’t arrived as mass invaders or hordes or big clans — these are individual families who are already four or five generations on Roman territory”, says population geneticist and anthropologist Joachim Burger, who co-authored the analysis. They probably saw themselves as Romans, he adds.

Do octopus brains work like humans’ — or is there another way to be smart?

Like us and our big-brained vertebrate relations, cuttlefish, squid and octopuses have excellent memories, use tools and are adept problem-solvers; they have a concept of time and are capable of delayed gratification. But they are not like us. “It’s hard to convey how different [the cephalopod brain] is,” says neuroscientist Cristopher Niell. “We just have no idea of how it functions.” Figuring it out could help us to understand where intelligence comes from. But working with a soft, flexible and wily creature — for which we have few ways to relieve pain — is a challenge for neuroscientists.