New CRISPR tools can cut, splice whole chromosomes

Experts are saying it's a "huge step forward for synthetic biology."

New CRISPR tools can cut, splice whole chromosomes
Pixabay
  • Until recently, the gene-editing tool CRISPR has only been able to make changes within single genes.
  • The new tools allow scientists to cut and splice larger chunks of genetic material.
  • The findings will likely have major implications for a variety of research fields, and also allow researchers to create synthetic species that can produce molecules not made by natural organisms.


Since 2012, the gene-editing tool CRISPR/Cas9 has enabled scientists to target and modify DNA with remarkable precision. But one constraint of this technique has been that it's only able to make changes within single genes. Now, scientists have developed new tools that allow them to cut and splice large chunks of chromosomes, and to assemble new synthetic genomes from distinct strains.

The findings, published in a paper on August 30 in Science, likely have major implications for fields such as synthetic biology, computational biology, and biological computing, and could lead to better treatments for a wide array of diseases.

"This new paper is incredibly exciting and a huge step forward for synthetic biology," Anne Meyer, a synthetic biologist at the University of Rochester in New York who was not involved in the paper, told Science.

Unlike previous gene-editing tools, the new tools are able to make many precise cuts to long strands of DNA without leaving any scarring.

The researchers, as Robert F. Service wrote for Science, also altered "another well-known tool, an enzyme called lambda red recombinase, so it could glue the ends of the original chromosome—minus the removed portion—back together, as well as fuse the ends of the removed portion. Both circular strands of DNA are protected from endonucleases. The technique can create different circular chromosome pairs in other cells, and researchers can then swap chromosomes at will, eventually inserting whatever chunk they choose into the original genome."

"Now, I can make a series of changes in one segment and then another and combine them together. That's a big deal," Chang Liu, a synthetic biologist at the University of California, Irvine, told Science.

Why CRISPR Gene Editing Gives Its Creator Nightmares

The new tools will likely open the doors for scientists to explore many novel areas: create synthetic species that can produce molecules not made by natural organisms, write information into DNA for use as a storage device, and drive down the costs of medical research by making it easier to edit bacterial genomes on a larger scale.

However, using CRISPR to edit large sections of the human genome is unlikely to occur anytime soon, given the regulatory hurdles and ethical complications. After all, scientists aren't fully aware of the consequences of making small edits to DNA, much less larger cuts.

"We don't always fully understand the changes we're making," Alan Regenberg, a bioethicist at Johns Hopkins Berman Institute of Bioethics, told Science News. "Even if we do make the changes we want to make, there's still question about whether it will do what we want and not do things we don't want."

This is what aliens would 'hear' if they flew by Earth

A Mercury-bound spacecraft's noisy flyby of our home planet.

Image source: sdecoret on Shutterstock/ESA/Big Think
Surprising Science
  • There is no sound in space, but if there was, this is what it might sound like passing by Earth.
  • A spacecraft bound for Mercury recorded data while swinging around our planet, and that data was converted into sound.
  • Yes, in space no one can hear you scream, but this is still some chill stuff.

First off, let's be clear what we mean by "hear" here. (Here, here!)

Sound, as we know it, requires air. What our ears capture is actually oscillating waves of fluctuating air pressure. Cilia, fibers in our ears, respond to these fluctuations by firing off corresponding clusters of tones at different pitches to our brains. This is what we perceive as sound.

All of which is to say, sound requires air, and space is notoriously void of that. So, in terms of human-perceivable sound, it's silent out there. Nonetheless, there can be cyclical events in space — such as oscillating values in streams of captured data — that can be mapped to pitches, and thus made audible.

BepiColombo

Image source: European Space Agency

The European Space Agency's BepiColombo spacecraft took off from Kourou, French Guyana on October 20, 2019, on its way to Mercury. To reduce its speed for the proper trajectory to Mercury, BepiColombo executed a "gravity-assist flyby," slinging itself around the Earth before leaving home. Over the course of its 34-minute flyby, its two data recorders captured five data sets that Italy's National Institute for Astrophysics (INAF) enhanced and converted into sound waves.

Into and out of Earth's shadow

In April, BepiColombo began its closest approach to Earth, ranging from 256,393 kilometers (159,315 miles) to 129,488 kilometers (80,460 miles) away. The audio above starts as BepiColombo begins to sneak into the Earth's shadow facing away from the sun.

The data was captured by BepiColombo's Italian Spring Accelerometer (ISA) instrument. Says Carmelo Magnafico of the ISA team, "When the spacecraft enters the shadow and the force of the Sun disappears, we can hear a slight vibration. The solar panels, previously flexed by the Sun, then find a new balance. Upon exiting the shadow, we can hear the effect again."

In addition to making for some cool sounds, the phenomenon allowed the ISA team to confirm just how sensitive their instrument is. "This is an extraordinary situation," says Carmelo. "Since we started the cruise, we have only been in direct sunshine, so we did not have the possibility to check effectively whether our instrument is measuring the variations of the force of the sunlight."

When the craft arrives at Mercury, the ISA will be tasked with studying the planets gravity.

Magentosphere melody

The second clip is derived from data captured by BepiColombo's MPO-MAG magnetometer, AKA MERMAG, as the craft traveled through Earth's magnetosphere, the area surrounding the planet that's determined by the its magnetic field.

BepiColombo eventually entered the hellish mangentosheath, the region battered by cosmic plasma from the sun before the craft passed into the relatively peaceful magentopause that marks the transition between the magnetosphere and Earth's own magnetic field.

MERMAG will map Mercury's magnetosphere, as well as the magnetic state of the planet's interior. As a secondary objective, it will assess the interaction of the solar wind, Mercury's magnetic field, and the planet, analyzing the dynamics of the magnetosphere and its interaction with Mercury.

Recording session over, BepiColombo is now slipping through space silently with its arrival at Mercury planned for 2025.

Study helps explain why motivation to learn declines with age

Research suggests that aging affects a brain circuit critical for learning and decision-making.

Photo by Reinhart Julian on Unsplash
Mind & Brain

As people age, they often lose their motivation to learn new things or engage in everyday activities. In a study of mice, MIT neuroscientists have now identified a brain circuit that is critical for maintaining this kind of motivation.

Keep reading Show less

End gerrymandering? Here’s a radical solution

Why not just divide the United States in slices of equal population?

The contiguous U.S., horizontally divided into deciles (ten bands of equal population).

Image: u/curiouskip, reproduced with kind permission.
Strange Maps
  • Slicing up the country in 10 strips of equal population produces two bizarre maps.
  • Seattle is the biggest city in the emptiest longitudinal band, San Antonio rules the largest north-south slice.
  • Curiously, six cities are the 'capitals' of both their horizontal and vertical deciles.
Keep reading Show less
Surprising Science

Scientists discover why fish evolved limbs and left water

Researchers find a key clue to the evolution of bony fish and tetrapods.

Scroll down to load more…
Quantcast