CRISPR in the classroom – New York Times

A decade after CRISPR began to become a major tool in genetic research, a new generation of scientists is growing up with the technology. Even high school students are able to take the CRISPR test. Some specialized public high schools teach CRISPR as a hands-on lesson in biotechnology. These classes cover options ranging from molecular biology to piping 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 Katie Gazda, a high school biotechnology teacher who taught CRISPR in her classroom last year. To help students better understand complex molecular dynamics, teachers use tools such as paper models, 3-D printed models, and online animation.







Note: The image is simplified.

1. Target the right genes

Scientists engineer a portion of RNA that matches the DNA they want to edit. This is called Guide RNA. The free bioinformatics search tool that scientists use for research allows students to practice designing their own guide RNA sequences.

2. Aim

Called an enzyme Cas9 Binds to a piece of DNA and temporarily loosens a piece of DNA. Students can model the process with paper cutouts, pushing the DNA sequence of a paper along the printed guide RNA until they match.

3. DNA cut

If the guide RNA matches one part of the DNA, the CAS9 enzyme DNA cuts off both strands of the double helix. An interactive animation from the Howard Hughes Medical Institute shows students how the Cas9 enzyme changes its shape and snaps through DNA.





DNA repair Including edited sections

DNA fragments Cut by Cas9

DNA fragments Cut by Cas9

DNA repair Including edited sections


Note: Images are simplified.

4. Repair and edit DNA

The equipment inside the cell rushes to fix the broken DNA. A repair process looks similar, using seamless pieces of DNA as a template to sew the broken pieces together.

Scientists can introduce tailor-made DNA into cells – using engineered DNA as a template to sew broken pieces together.

Students also learn about real-life examples of DNA editing, such as therapy for genetic disorders, including sickle cell disease and cystic fibrosis. In some practices, they may look at examples of actual DNA sequences associated with each disease and evaluate specific gene modifications proposed for the cure of the disease.

Editing genes with bacteria

Mrs Gazda believes that hands-on lab lessons help students “open their minds to the idea that they can really be a scientist.” Several companies sell CRISPR curriculum kits in high schools and universities. A kit from life science technology maker Bio-Rad includes a prepackaged test using E. coli bacteria.





Modifying bacteria with CRISPR

E. coli

Bacterial colony

Petrie

The dishes are full

Bacterial food

Petrie

The dish is full

Bacterial food

Modifying bacteria with CRISPR

Petrie

The dish is full

Bacterial food


Bacteria without CRISPR





A gene in bacteria encodes an enzyme called gal-gal, which can help break down specific molecules.

When X-gal is broken by gal-gal a bright blue color is seen.

A gene in bacteria encodes an enzyme called gal-gal, which can help break down specific molecules.

A bright blue color

X-gal appears

broken by ß-gal


Note: Diagrams and molecular names are simplified.

The E. coli bacteria used in bio-rad kits grow in a food mixture that contains a compound X-cheek. Typically, these bacteria are able to use an enzyme to divide the compound into two parts: a sugar molecule and an indicator molecule.

The indicator molecule turns deep blue, which shows the students that the bacterial enzyme is working. This color display is an important part of the experiment. It shows students what to expect in an unchanged, or “control” group – an important part of any scientific experiment.

Modifying bacteria with CRISPR





ß-gal enzymes are not produced.

The X-gal compound cannot be broken down without the ß-gal enzyme, so bright blue indicating molecules are never formed.

After students use CRISPR to convert a part of the gene, the gene no longer works.

After students use CRISPR to convert a part of the gene, the gene no longer works.

ß-gal enzymes are not produced. The X-gal compound cannot be broken down without the ß-gal enzyme, so bright blue indicating molecules are never formed.


Note: Diagrams and molecular names are simplified.

The process of transforming E. coli DNA with CRISPR involves lab techniques such as piping liquids and carefully removing bacterial colonies. Teaching a new lab class like CRISPR can be intimidating, says Gregory Jubulis, a high school science teacher who uses a bio-rad kit in his biotechnology class. “It takes you a few years to feel really comfortable teaching something,” he said.

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

Not just about molecules

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

“Ethics always comes up,” Mr. Jubulis said of how he relates lab experiments to real-life CRISPR applications such as gene therapy. He has many student friends or family who have a genetic disorder, so the subject can be deeply personal.

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