Helen FieldsScience Writer

For today’s paper, I wrote about late blight – you may know it better as potato blight, the disease that caused the Irish Potato Famine. It’s still a huge problem for potato and tomato farmers, so a bunch of scientists sequenced its genome (their paper is in Nature today). Here’s my story.

Usually when I read about some new genome sequence, I get a big “eh” feeling. As in, “eh, big string of As, Gs, Cs, and Ts, who cares.” But this is a really cool disease, and super important economically, and it turns out the genome itself is interesting, too.

The organism that causes late blight has a ginormous genome, with a ton of repeating sequences of DNA. Those big repeaty areas include lots of copies of the nasty genes that help it attack plants, like genes that cause cell death and stuff. So maybe there’s some way that the bug is using those extra copies to overcome the plants’ defenses. Cool, huh?

Chad Nussbaum, the guy at the Broad Institute whose group did the sequencing, said this genome was really hard because of all the repeats – and it helped them figure out stuff they can use later. “Every genome teaches you something new,” he told me. “They’re all strange in their own little ways.”

Best thing I found while working on this story: PotatoPro, a news source for the potato processing industry with headlines like “Sultry Sally has re-launched its low fat potato chip with even less fat” and “Man dies after falling into potato harvester.”

Hey, another story! This one’s about a National Geographic grantee who’s studying a bunch of mongooses in a national park in Botswana who get the human version of tuberculosis. Which, it turns out, is really bad for mongooses.

When she found TB in mongooses a few years ago, it was the first time anyone had confirmed a human disease in free-ranging wildlife. This is one of those “firsts” where you have to pay attention to the adjectives. Domesticated animals and zoo animals are already known to get human diseases. (It’s still a big deal, though – made quite a splash in the epidemiology world a few years back.)

This story made me wonder about the plural of mongoose. My Webster’s New World Dictionary only gives one plural: mongooses. My Webster’s New Collegiate lists mongooses first, but also mongeese. And when the vet who actually did the research talks about them, she uses mongoose as the singular and plural. I settled on mongooses and the copy editors at National Geographic News seem to agree with me.