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Tuesday, July 25, 2000
By Michael Woods, Post-Gazette National Bureau
BAR HARBOR, Maine -- Would a hereditary disease have killed Abraham Lincoln within a year even if John Wilkes Booth's bullet had missed?
Scientists are poised to move ahead with genetic tests on specimens of Lincoln's blood, bones, and hair to answer the question, according to the chairman of an expert panel that gave a preliminary go-ahead in the 1990s.
"I do think we're ready now," Dr. Victor A. McKusick, a genetics expert from Johns Hopkins University School of Medicine in Baltimore, said.
"We've accumulated a great deal of new information about the Marfan syndrome gene. There's a much better chance of getting a definitive answer."
McKusick was among a group of scientists attending a genetics seminar at the Jackson Laboratory, a noted research center.
Lincoln's physical appearance led modern scientists to hypothesize that the 16th president suffered from the genetic disorder Marfan syndrome. At 6 feet, 4 inches tall, Lincoln was unusually tall with limbs out of proportion to the rest of his body.
He had other typical features of Marfan syndrome, such as long, bony fingers; unusually large feet; a gaunt, elongated face with large ears and nose; and a sunken chest.
The relatively rare condition, which occurs in about one out of every 10,000 people today, can lead to a fatal heart and blood vessel defects.
Marfan syndrome is perhaps best known for causing the deaths of Olympic volleyball star Flo Hyman and University of Maryland basketball player Chris Patton.
Based on historical records, doctors have speculated that the effects of Marfan syndrome were reaching a peak in the 56-year-old president. They believe Lincoln's heart was failing before the 1865 assassination, and that he could not have lived more than six to 12 months.
In 1991, scientists from Jefferson Medical College in Philadelphia got preliminary approval from McKusick's panel to test Lincoln's DNA for the gene that causes Marfan syndrome. The panel was organized by the National Museum of Health and Medicine in Washington, D. C., which is part of the Armed Forces Institute of Pathology.
The museum's displays include fragments of bone from Lincoln's skull and strands of hair removed during the Lincoln autopsy. Also preserved in the museum are bloodstains from the cuffs of a shirt worn by one of the physicians.
Scientists realized that genetic technology made it possible to copy DNA from the samples, and analyze it for the gene abnormality that causes Marfan syndrome.
DNA is the double-stranded molecule of heredity that makes up genes.
The panel concluded that there was no legal or ethical problem in doing the tests. Any new information about Lincoln would be important historically. In addition, it found that the tests could help in broadening public understanding of hereditary disorders and boost the self-esteem of individuals with Marfan syndrome.
In a later report, however, the panel recommended that tests should be delayed until researchers learned more about the chemical structure of the Marfan gene.
Panel members were concerned that tests with then-incomplete knowledge would destroy some of the precious samples, without providing a conclusive answer to the question.
McKusick said scientists had obtained detailed information about the structure of the gene during the last eight years. The gene makes a protein called fibrillin, critical for normal body development.
In Marfan syndrome, parts of the chemical recipe for fibrillin are altered, or mutated, in ways that result in characteristic physical appearance and health problems. Checking the Lincoln specimens could show definitively whether the mutated gene is present, he added.
McKusick said he had been in contact with the Defense Department, which operates the health and medicine museum, about making the Lincoln specimens available to scientists.