Mark Johnson and Kathleen Gallagher of the Milwaukee Journal Sentinel won in the large newspaper category for “One in a Billion,” a compelling series about the use of genomics to find the cause of an unknown disease that was eating away at the gut of four-year-old Nicholas Volker. Robert Lee Hotz, a science writer for The Wall Street Journal who served on the judging panel, called the series “a richly reported and brilliantly told epic of biomedicine.”

“From the day we began working on ‘One in a Billion,’ we knew that understanding and explaining the science would be enormously challenging,” Johnson said. “It was a wonderful learning experience and deeply rewarding.” The series also won a Pulitzer Prize.

Johnson and Gallagher told about the use of DNA gene sequencing methods to reveal the entire genetic script of a sick child in hopes of finding clues to the cause of his debilitating disease. A small team of scientists sifted through more than 16,000 variations in the boy’s genetic script to find a single mutation on his X chromosome that proved to be the cause of the baffling illness in his gut. The reporters described both the promise and the limitations of genetic technology. The boy received a cord blood transplant to treat a rare immune system disorder from which he also suffers, but it is unclear what the transplant will mean for the illness that ravaged his intestine. Hotz of The Wall Street Journal said the winners “have set the standard for 21st century science writing” with their complex and nuanced story.