Research of Amish baby disorder could prevent brain defects
WASHINGTON (AP) – A newly discovered fatal gene mutation, found only in Amish newborns, could be a major first step toward helping scientists prevent brain defects in babies worldwide, scientists said Tuesday. The genetic disorder, known as Amish microcephaly, is specific to the Old Order Amish community in Lancaster County, Pa., where it has been traced back nine generations to one couple. It amounts to a breakdown in DNA creation that causes abnormally small heads and brains in fetuses and, eventually, death.
New information on the disorder – the result of a 21/2-year study by the National Genome Research Institute in Bethesda, Md. – could help doctors find ways to stop the DNA breakdown in other kinds of brain defects in newborns.
The study is the first of its kind to link problems with DNA production to fetal brain development, said Dr. Leslie Biesecker, the report’s lead author, a senior investigator at the Institute’s Genetic Disease Research Branch. It was first reported in the September issue of “Nature Genetics.”
“What this disease appears to be is the inability to move those (DNA) building blocks into a particular place of the cell where they need to be,” Biesecker said.
“What we have to do is see if we can manipulate that, and supplement or do other medical tricks to get around that problem.”
In Lancaster County, where about 20,000 Amish people descend from only a few dozen who settled there in the 1700s from Germany, 61 babies from 23 families have had the disorder in the last 40 years. Most of the babies died in their first six months; none survived more than 14 months.
There is no known treatment or cure.
Dr. D. Holmes Morton, who heads the Clinic for Special Children in Strasburg, Pa., and helped write the study, said he has cared for more than 20 Amish babies with the disorder since 1988.
He sees as many as three new cases every year.
“It’s a disorder that has shown up in the community for many, many generations,” Morton said.
“The Amish people knew about it, but very few other people had seen it.”
Interestingly, Morton said, the DNA breakdown does not affect development in other parts of the fetus, which means that babies born with the defect have normal and healthy hearts, livers, kidneys, and other vital organs. That suggests that the DNA building blocks – specifically, a nucleic acid – are being received in developing cells in other parts of the body.
“It’s precisely that kind of thinking about a mutation and about a mechanism of a disease like this that lets us think of possibilities about how you get around it,” Morton said.
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On the Net: National Human Genome Research Institute: http://genome.gov/
The Clinic For Special Children: http://www.clinicforspecialchildren.org/