Like many family reunions, yesterday's Mattingly family gathering in Solomons in Calvert County was a time for distant relatives to catch up with one another, to eat, drink and gab.
But they also took out time for neurological exams and blood tests.
For more than 300 years, the Mattinglys have been passing a debilitating muscular disorder from generation to generation, and a team of doctors took advantage of the reunion to try to learn more about their ailment and possibly to locate the gene that causes it.
The rare disease has no formal name, although its symptoms and effects sometimes resemble those of other muscle diseases. There is no cure.
Andrew Mattingly Jackson, of Hampstead, who organized the event, said he hopes the gathering will lead to a better understanding of the disease, which starts as a slight muscle weakness and then slowly gets worse.
Mr. Jackson, 66, must use an electric-powered wheelchair and his arms and hands have wasted to the point where he can't feed himself. No treatment exists.
"My father had the disease, and one of my sons has the disease. I am from a family of 11 children, and three of the boys had the disease. Plenty of girls get the disease, though there are none in my immediate family," the Carroll County man said.
The event brought together more than 80 Mattinglys yesterday, with 50 more scheduled to show up today. Some, like Mr. Jackson, use wheelchairs; others need to use walkers or canes.
Other Mattinglys had similar stories to tell.
Bonnie Beardsly, 46, of Columbia, whose father was John Mattingly, said she has the disease, as well as her 19-year-old son, her father and grandfather.
"All my life, as a child I was not able to run fast or jump high as everyone else," she said. "Now my legs are weak, which makes it difficult to get up stairs."
Trying to find the culprit are researchers that include Drs. David R. Cornblath, John W. Griffin and Bruce Rabin, all neurologists from the Johns Hopkins School of Medicine in Baltimore, as well as two geneticists from Children's Hospital of Philadelphia.
Dr. Cornblath said the disease is caused by a dominant gene, because about 50 percent of the offspring of Mattinglys who have the disease also suffer from it.
"Because this family is so large, and so many members have the disease, this is a unique opportunity to do the kind of work that will tell us what the gene is and what its products are, to figure out how the cells do not work and why not," he said.
In the 1960s, the disease was diagnosed as Charcot-Marie-Tooth or CMT, a muscular disorder named for the three French scientists who discovered it. But advances in technology have helped researchers find many of the defective genes that cause CMT, and those same defects are not present in the Mattinglys.
Dr. Cornblath said the disease has more similarities to amyotrophic lateral sclerosis, or ALS, the disease that killed Yankees Hall of Famer Lou Gehrig. But unlike ALS, the Mattingly disease does not attack internal organs and, therefore, is not fatal.
Dr. Cornblath said he hopes the blood samples his team gathers will help pinpoint the chromosome that causes the disease in the next year, although finding the individual gene could take much longer. The research has been paid for in part by the Muscular Dystrophy Association.