Tomatoes come in all kinds of colors, sizes, and flavors. But what’s going on at the genetic level? What makes a tomato red or yellow? Tiny or giant?

Researchers are mapping the genomes of 22 varieties of nightshades—the family of plants that includes tomatoes, potatoes, and eggplants. They located the genes that control the size of tomatoes and eggplants and then used CRISPR gene editing to grow bigger fruits without sacrificing flavor.

Geneticist Michael Schatz joins Host Ira Flatow to talk about his latest research into nightshade genomes and the current state of genetically modified crops.

Guest: Dr. Michael Schatz, professor of computational biology and oncology at Johns Hopkins University, based in Baltimore, Maryland.

Transcript will be available after the show airs on sciencefriday.com.

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