Scientists tap DNA to verify gender of 4,000-year- old remains

In 1915, a team of U.S. archaeologists excavating the ancient Egyptian necropolis of Deir el-Bersha blasted into a hidden tomb. Inside the cramped limestone chamber, they were greeted by a gruesome sight: a mummy’s severed head perched on a cedar coffin.

The room, which the researchers labeled Tomb 10A, was the final resting place for a governor named Djehutynakht and his wife. At some point during the couple’s 4,000-year slumber, grave robbers had ransacked the burial chamber and plundered its gold and jewels. The looters tossed a headless, limbless mummified torso into a corner before attempting to set the room on fire to cover their tracks.

The archaeologists went on to recover painted coffins and wooden figurines that survived the raid and sent them to the Museum of Fine Arts, Boston, in 1921. Most of the collection stayed in storage until 2009 when the museum exhibited it. Though the torso remained in Egypt, the decapitated head became the star of the showcase. With its painted-on eyebrows, somber expression and wavy brown hair peeking through its tattered bandages, the mummy’s noggin brought viewers face-to-face with a mystery.

“The head had been found on the This mummified head was found on top of a coffin after grave robbers looted the tomb of Governor Djehutynakht and his wife, who were believed to have lived around 2000 B.C. in Egypt. For years, it was unclear whether the head was his or hers.

governor’s coffin, but we were never sure if it was his head or her head,” said Rita Freed, a curator at the museum.

The museum staff concluded only a DNA test would determine whether they had put Mr. or Mrs. Djehutynakht on display.

Egyptian mummies pose a unique challenge because the desert’s scorching climate rapidly degrades DNA. Earlier attempts at obtaining their ancient DNA either failed or produced results contaminated by modern DNA. To crack the case, the museum turned to the Federal Bureau of Investigation.

The FBI had never before worked on a specimen so old. If its scientists could extract genetic material from the 4,000-year-old mummy, they would add a powerful DNA collecting technique to their forensics arsenal and also unlock a new way of deciphering Egypt’s ancient past.

‘‘I honestly didn’t expect it to work because, at the time, there was this belief that it was not possible to get DNA from ancient Egyptian remains,’’ said Odile Loreille, a forensic scientist at the FBI. But in the journal “Genes” in March, Loreille and her colleagues reported that they had retrieved ancient DNA from the head. And after more than a century of uncertainty, the mystery of the mummy’s identity had been laid to rest.

In Tomb 10A

Governor Djehutynakht and Lady Djehutynakht are believed to have lived around 2000 B.C. during Egypt’s Middle Kingdom. They ruled a province of Upper Egypt. Though the walls in their tomb were bare, the coffins were Considering clues about the curls

Every day is a curly hair day for sheep. Those curls and kinks are part of what makes woolen sweaters so cozy — the maze of fibers helps trap warm air, keeping it close to the body. But wrapped up in those curls might also be answers to a long-standing mystery: Exactly how does a strand of hair wind itself into a curl?

Researchers clipped samples from six New Zealand merino sheep to find out. After testing several theories, they discovered that there are two types of cells that make up wool fibers, one long and one short. A certain proportion of longer cells to shorter cells, arranged on either side of the strand, generates a curl.

A hat trick could be a killer

Canadian fans take their hockey seriously — so much so, it appears, that heart attack rates go up the day after a game.

Researchers looked at data on heart attack admissions to a Montreal hospital from June 2010 to December 2014. There were 2,199 admissions, or an average 1.3 per day, about a quarter of them in women. Then they checked data on admissions for each day after the Montreal Canadiens played. On the day after a game, admissions for men increased to 1.9 a day from 1.0, though women’s numbers remained the same.

In the whole population, there was a 15 percent rise in admissions on the day after the team won, but none after a loss. Men younger than 55 were particularly susceptible, with an increased risk of 40 percent on days after a victory, and 20 percent after a defeat.