Cockroach Genome Shows Why They Are Impossible to Kill

Jason Daley in Smithsonian Magazine:

American_roachNo matter how you feel about them, cockroaches are something special. Cut a few legs off a nymph, and they grow back. Leave a few cookie crumbs in the carpet, and the critters seem to instantly zero in on them. Expose them to fecal material, bacteria and other pathogens, homemade antibiotics will keep them healthy. On top of it all, they can eat just about anything, live in brutal conditions and laugh in the face of the toughest insecticides.

So what gives them these seeming superpowers? As Maggie Fox at NBC News reports, a new study suggests the answer is in their genes. Researchers at the Chinese Academy of Sciences in Shanghai sequenced the genome of the American cockroach, Periplaneta Americana, revealing a Swiss army knife-like set of genes that makes the insects uber adaptable.

It turns out that cockroaches have a massive genome; of the insects yet studied, the cockroach is second only to the locust. The genes of the American cockroach—which isn’t really American: it was likely transported to the Americas from Africa as early as 1625—is more closely related to termites than to the German cockroach, another major house pest that had its genome sequenced earlier this year. That’s not surprising, since termites turn out to be “eusocial cockroaches” and were moved into the same order as roaches earlier this year.

GenomeWeb reports that 60 percent of the cockroach’s genome contains repetitive elements. But it also includes 21,336 protein-encoding genes, 95 percent of which actually produce proteins. Many of those genes give cockroaches the tools to survive in urban environments.

More here.