MINNEAPOLIS — Abraham Lincoln’s appearance and historical documents that note his especially clumsy gait have long caused researchers to puzzle over whether he may have had a genetic disorder called Marfan syndrome.
Now, members of the beloved president’s family tree are wondering if Lincoln had a different, incurable hereditary disease called ataxia that affects the coordination it takes to walk, write, speak and swallow.
Researchers at the University of Minnesota have discovered a gene mutation in 11 generations of relatives who descended from Lincoln’s grandparents, and they say there’s a 25 percent chance that Lincoln also inherited the gene, said Laura Ranum, a genetics professor who led the research.
“Because the historical literature talks about his clumsy gait ... it raises the possibility that that was caused by a mutation in this gene,” Ranum said.
But since Lincoln has no living direct descendants, confirming whether the nation’s 16th president had the defective gene would require that his DNA be taken from historical artifacts and tested — an issue that has been debated over the years.
“What historical purpose would it serve? It (wouldn’t) change the facts of how he became a great president,” said Kim Bauer, Lincoln curator at the Abraham Lincoln Presidential Library and Museum in Springfield, Ill. “I would fall on the side of leaving President Lincoln alone.”
'Lighten up on disabled people'
The new findings on the ataxia gene were reported this week in the online edition of the journal Nature Genetics. Since 1992, the Minnesota researchers have studied more than 300 members of the Lincoln family. About one-third of them have ataxia.
“If a president had it, and he was disabled but still running the country, maybe people would lighten up on disabled people a little bit,” said Smith, 57, of Manteca, Calif., who said he was once arrested for drunken driving because of the disease’s symptoms.
Crary, 50, of Prescott, Ariz., said she has vertigo and had to have reconstructive surgery on her shoulder after losing her coordination and falling. If Lincoln had ataxia, that could offer hope for others suffering from it. About 150,000 Americans have the degenerative disease.
“Look what he achieved, even if he had this defective gene,” Crary said.
In the 1990s, a geneticist asked the National Museum of Health and Medicine to test Lincoln’s hair and bones to find out if the president had Marfan syndrome, a disorder that affects connective tissue, blood vessels and eyes, and can produce fatal abnormalities of major arteries. Marfan’s sufferers often have unusual height and elongated fingers, toes and limbs — all characteristics of Lincoln.
Don't miss these Health stories
More women opting for preventive mastectomy - but should they be?
Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.
- Larry Page's damaged vocal cords: Treatment comes with trade-offs
- Report questioning salt guidelines riles heart experts
- CDC: 2012 was deadliest year for West Nile in US
- What stresses moms most? Themselves, survey says
- More women opting for preventive mastectomy - but should they be?
But multiple panels decided “the greater public good is served by not destroying this non-renewable national historic treasure,” according to the museum’s Web site.
Bauer, the Lincoln museum curator, said that when Lincoln’s tomb was renovated about 100 years ago, his last living son made it clear he did not want his father’s remains disturbed.
That should be an overriding factor, Bauer said.
“His last living descendant, still alive, saying, ’Don’t bother my father anymore.’ ... If DNA testing was alive in the early 1900s, I think he would say the same thing,” he said.
Ranum said researchers would need a small amount of Lincoln’s DNA to test for the gene, which causes spinocerebellar ataxia type 5, or SCA5. The DNA could be found on a bloodstained garment or a hair sample.
Dr. Robert Y. Moore, a movement disorder specialist and a professor of neurology at the University of Pittsburgh, said the Minnesota research breaks ground “from the perspective that this is a mutation in a gene that has not been known to be involved in this sort of thing before.”
For now, Ranum said the new discovery should lead to better diagnosis and possible future treatments and may help people decide whether to have children. The mutated gene is dominant, so there is a 50 percent chance a parent will pass it on.
Still, she said finding out whether Lincoln had the gene could help destigmatize the disease.
“Every aspect of Lincoln’s life has been gone over with a fine-tooth comb,” she said. “I think it is of historical interest.”
© 2013 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.