More than 1 million people died over the course of Ireland’s Great Famine between 1845 and 1852. We know, of course, that a blight had wiped out an entire species of potato — a staple of the Irish diet. But precisely what strain of the blight pathogen it was, exactly, had remained a mystery … until now.
Now, scientific and historical two-for-one, researchers have used dried potato leaves from herbariums to sequence the genome of the pathogen that caused the Great Famine. The culprit was a single strain of the fungus-like pathogen Phytophthora infestans — and not the common strain that was long the prime suspect.This marks the first time scientists have used dried leaves to decode the genome of a plant pathogen.
Those worried about a resurgence of the dreaded potato blight can breathe a sigh of relief: the strain of potato blight in question is extinct.
The study opens up a new avenue of genomics research using dried leaves from herbariums, which have proven to be a good source of DNA.
Read more about the discovery in these stories:
- “How Genomics Solved The Mystery Of Ireland’s Great Famine,” Lydia Zuraw | NPR
- “The Great Famine: Decoded,” Ann Gibbons | Science NOW
- “Mystery cause of Irish potato famine finally solved,” John Platt | Mother Nature Network
- “Irish potato famine pathogen identified,” Helen Briggs | BBC News