Lifeboat Foundation

Scientists with the Human Pangenome Reference Consortium have made groundbreaking progress in characterizing the fraction of human DNA that varies between individuals. They have assembled genomic sequences of 47 people from around the world into a so-called pangenome in which more than 99 percent of each sequence is rendered with high accuracy.

For two decades, scientists have relied on the human reference genome as a standard to compare against other genetic data. Thanks to this reference genome, it was possible to identify genes implicated in specific diseases and trace the evolution of human traits, among other things.

However, it has always been a flawed tool: 70% of its data came from a single man of predominantly African-European background whose DNA was sequenced during the Human Genome Project. Hence, it can reveal very little about individuals on this planet who are different from each other, creating an inherent bias in biomedical data believed to be responsible for some of the health disparities affecting patients today.

A spinning plasma ring mimics the rotating structure surrounding a black hole.

Astrophysicists have many questions about the so-called accretion disk that forms from plasma and other matter falling into a black hole. Now researchers have generated a rotating ring of plasma in an unconfined arrangement in the lab, which will enable more realistic studies of plasma in astrophysical disks [1]. The lab plasma also produced a jet perpendicular to the disk, as real black holes do. The experiment could provide a platform for testing theories describing the evolution of astrophysical disks.

According to observations, the matter in a black hole accretion disk spirals inward at a rate that is thousands of times faster than would be expected from turbulence-free rotation. The leading explanation involves turbulence generated in part by the interaction of magnetic fields with the plasma in the disk, but this theory is difficult to test without a lab plasma that rotates rapidly. Such an experimental system would also allow researchers to investigate accretion disks around massive objects other than black holes.

In a major advance, scientists have assembled genomic sequences of 47 people from diverse backgrounds to create a pangenome, which offers a more accurate representation of human genetic diversity than the existing reference genome. This new pangenome will help researchers refine their understanding of the link between genes and diseases, and could ultimately help address health disparities.

For more than 20 years, scientists have relied on the human reference genome, a consensus genetic sequence, as a standard against which to compare other genetic data. Used in countless studies, the reference genome has made it possible to identify genes implicated in specific diseases and trace the evolution of human traits, among other things.

But it has always been a flawed tool. One of its biggest problems is that about 70 percent of its data came from a single man of predominantly African-European background whose DNA.

Exceptionally well-preserved fossils from the Cambrian period have helped fill a gap in our understanding of the origin and evolution of major animal groups alive today.

A new analysis of fossils belonging to an extinct invertebrate called Rotadiscus grandis have helped place this species in the animal tree of life, revealing how some characteristics of living species may have evolved independently rather than originating in a single common ancestor.

Half a billion years ago, an unusual-looking animal crawled over the sea floor, using tentacles to pick up food particles along the way.

A study of the mechanical forces in certain immune cells may give new insights into how organisms deal with ever-evolving pathogens.

To fight disease, many organisms have an adaptive immune system, which learns the molecular shapes of foreign elements (antigens) and remembers them to mount a defense against future infections. In vertebrates, the learning stage involves a remarkable cycle of evolution within an individual animal—a cycle called affinity maturation, which involves a type of immune cell called a B cell (Fig. 1). In this process, B cells are selected to have receptors that bind strongly to specific antigens. However, if these cells become too specialized, they risk becoming unresponsive to slightly mutated pathogens. Fortunately, the immune system can limit affinity maturation to retain a range of specificities for target pathogens. Just how the immune system is able to do that is the subject of a fascinating new study by Hongda Jiang and Shenshen Wang from the University of California, Los Angeles [1].

Mathematicians have uncovered a universal explanatory framework that provides a “window into evolution.” This framework explains how molecules interact with each other in adapting to changing conditions while still maintaining tight control over essential properties that are crucial for survival.

According to Dr. Araujo from the QUT School of Mathematical Sciences, the research results provide a blueprint for the creation of signaling networks that are capable of adapting across all life forms and for the design of synthetic biological systems.

“Our study considers a process called robust perfect adaptation (RPA) whereby biological systems, from individual cells to entire organisms, maintain important molecules within narrow concentration ranges despite continually being bombarded with disturbances to the system,” Dr. Araujo said.

Like treasured recipes passed down from generation to generation, there are just some regions of DNA that evolution doesn’t dare tweak. Mammals far and wide share a variety of such encoded sequences, for example, which have remained untouched for millions of years.

Humans are a strange exception to this club. For some reason, recipes long preserved by our ancient ancestors were suddenly ‘spiced up’ within a short evolutionary period of time.

Because we’re the only species in which these regions have been rewritten so rapidly, they are called ‘human accelerated regions’ (or HARs). What’s more, scientists think at least some HARs could be behind many of the qualities that set humans apart from their close relatives, like chimpanzees and bonobos.

Forget about evolution, climate change or vaccines – what makes people really lose their mind, apparently, is cats.

“We’ve had posts that have affected people’s lives in a very substantial way, including posts that went beyond the virtual world. People really got threats or disrespectful comments,” says Yomiran Nissan.

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Discovery could help plug gaps in understanding of evolution after Cambrian explosion more than 500m years ago.