CRISPR in the Classroom – The New York Times

A decade after CRISPR started to become a major tool in genetic research, a new generation of scientists is growing up with technology. Even high school students are capable of conducting CRISPR experiments. Some specialized public high schools teach CRISPR as a practical lesson in biotechnology. These courses cover everything from molecular biology and pipetting to biomedical ethics and career options.

Visualize tiny molecules

“Visualizing and understanding what’s happening at the molecular level is usually always a challenge,” said Katy Gazda, a high school biotech teacher who taught CRISPR in her class last year. To help students better understand complex molecular motions, teachers use tools such as paper models, 3D printed models, and online animations.







Note: the diagram is simplified.

1. Targeting the right gene

Scientists design a piece of RNA that matches the DNA they want to modify. This is called the guide RNA. Students can practice designing their own guide RNA sequences using the same free bioinformatics research tool that scientists use for research.

2. Bind Target

An enzyme called Case9 binds to a piece of DNA and temporarily unwinds a section of the DNA. Students can model the process with paper cutouts, pushing a paper DNA sequence along a printed guide RNA until they match.

3. cut DNA

If the guide RNA matches a section of DNA, the Cas9 enzyme cuts both strands of the DNA double helix. An interactive animation from the Howard Hughes Medical Institute shows students how the Cas9 enzyme changes shape and cuts DNA.





DNA repaired with edited section

DNA fragments cut by Cas9

DNA fragments cut by Cas9

DNA repaired with edited section


Note: Diagrams are simplified.

4. Repair and modify DNA

The machinery inside the cell rushes to repair the broken DNA. A repair process uses a similar-looking, unbroken piece of DNA as a template to stitch the broken pieces back together.

Scientists can introduce tailor-made DNA into the cell, prompting the repair machinery to use the modified DNA as a template to put the broken pieces back together.

Students also learn about real-life examples of DNA editing, such as therapies for genetic diseases including sickle cell disease and cystic fibrosis. In some exercises, they can see examples of the actual DNA sequence associated with each disease and evaluate specific genetic changes proposed to cure the disease.

Convenient gene editing with bacteria

Ms Gazda thinks hands-on lab classes help students “open their minds to the idea that they really can be a scientist”. Several companies sell CRISPR program kits to high schools and universities. A kit from Bio-Rad, a maker of life science technologies, includes a prepackaged experiment using E. coli bacteria.





Bacteria modified with CRISPR

E.coli

bacteria colonies

Petri

dishes full of

bacterial food

Petri

dish full of

bacterial food

Bacteria modified with CRISPR

Petri

dish full of

bacterial food


Bacteria without CRISPR





A gene in bacteria codes for an enzyme, called ß-gal, that can help break down certain molecules.

A bright blue color appears when X-gal is broken down by ß-gal.

A gene in bacteria codes for an enzyme, called ß-gal, that can help break down certain molecules.

A bright blue color

appears when X-gal is

broken down into ß-gal.


Note: Diagrams and molecule names are simplified.

The E. coli bacteria used in the Bio-Rad kit are grown on a food mix that includes a compound called X-gal. Normally, these bacteria are able to use an enzyme to break the compound down into two parts: a sugar molecule and an indicator molecule.

The indicator molecule turns dark blue, showing students that the bacterial enzyme is working. This colorful display is an important part of the experience. It shows students what to expect in an unchanged or “control” group – an essential part of any science experiment.

Bacteria modified with CRISPR





The enzyme ß-gal is not produced.

The X-gal compound cannot be broken down without the β-gal enzyme, so the bright blue indicator molecule is never produced.

After students use CRISPR to transform a section of the gene, the gene is no longer functional.

After students use CRISPR to transform a section of the gene, the gene is no longer functional.

The enzyme ß-gal is not produced. The X-gal compound cannot be broken down without the β-gal enzyme, so the bright blue indicator molecule is never produced.


Note: Diagrams and molecule names are simplified.

The DNA modification process of E. coli with CRISPR involves laboratory techniques such as pipetting liquids and carefully moving colonies of bacteria. Teaching a new lab class like CRISPR can be daunting, says Gregory Jubulis, a high school science teacher who uses the Bio-Rad kit in his biotech class. “It takes you a few years before you’re really comfortable teaching something,” he said.

But when classroom CRISPR lab kits first became available, he knew he wanted to teach it. “I just want my kids to be ready for the future of science,” he said.

Not just on molecules

Ms. Gazda uses lab classes as an opportunity to share career options with students. In a CRISPR lab, students can discover careers in everything from molecular and cellular biology to entrepreneurship and science journalism.

“Ethics always come back,” says Jubulis, explaining how he connects lab experience to real-world CRISPR applications like gene therapy. Many of his students have friends or family with genetic conditions, so the topic can be deeply personal.

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