The genome of the frog, Xenopus tropicalis, fills a major gap among such vertebrates sequenced so far, said Uffe Hellsten, a researcher with Joint Genome Institute, Walnut Creek, Calif.
"When you look at segments of the Xenopus genome, you literally are looking at structures that are 360 million years old and were part of the genome of the last common ancestor of all birds, frogs, dinosaurs and mammals that ever roamed the earth," Hellsten said in a release from the Institute Thursday.
The clawed frog was among the last commonly used laboratory organisms to be sequenced after the mouse, chicken, nemotode, zebrafish and fruit fly, Hellsten and other scientists wrote in a recent issue of the journal Science.
The frogs are especially suited to laboratory work because their large eggs are easy to inject with chemicals, the scientists said.
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