Genaissance test rules out disorder in Schiavo autopsy
Abram Katz , Register Science Editor
06/17/2005
Terri Schiavo’s heart stopped 15 years ago, but recent tests by a Connecticut biotech company have ruled out abnormal cardiac rhythm as a cause of the collapse.
Medical examiners, family and friends may never know what happened to Schiavo in the early hours of Feb. 25, 1990.
She spent the rest of her life in a persistent vegetative state, unaware of the media circus and political maneuvering that accompanied her husband’s successful fight to stop her treatment in March.
Schiavo was autopsied on April 1 to determine the extent of her neurological damage, the cause of her 1990 episode, and to look for signs of abuse by her husband.
As part of the Florida medical examiner’s thorough post-mortem, Schiavo was tested to see if she may have died from a genetic heart cardiac problem called Long QT syndrome.
The diagnosis now can only be made by using the Familion Test by Genaissance Pharmaceuticals of New Haven.
According to Schiavo’s autopsy report, she did not possess the genetic mutations that foster Long QT and related syndromes.
Richard Judson, chief scientific officer of Genaissance, said the Familion Test checks DNA from the person in question.
Long QT has been traced by researchers at Yale and the University of Utah to five genes known to regulate the development of ion channels in heart muscle.
A mutation in any of the five can give rise to Long QT and the related Brugada syndrome.
Ion channels are essential for healthy functioning of the heart, Judson said.
At the beginning of a heartbeat, channels open and let sodium ions enter muscle cells. At about the same time, other channels allow potassium ions to leave the muscle cell.
The changing balance of ions creates a small voltage that responds to the heart’s signals, Judson said.
About 1 person in 5,000 has Long QT syndrome, which is dominant and heritable.
That means about 60,000 to 100,000 people in the U.S. carry a Long QT gene, he said.
The first symptom of the syndrome in 20 percent of patients is sudden death. Another symptom is fainting.
The Familion Test costs $5,400 and runs four blood samples in parallel to achieve precision.
Nevertheless, the test has a 25 percent false negative rate because other genes can also apparently cause Long QT, Judson said.
The test is most useful for determining whether children or relatives carry Long QT genes, Judson said. |
