基因变异与年青人猝死有关
http://www.100md.com
2000年12月12日
NEW YORK (Reuters Health) - A mutation in a calcium-controlling gene is responsible for at least some cases of a relatively rare condition in which children have fainting spells and a rapid heartbeat in response to stress, according to a report.
The condition, known catecholaminergic polymorphic ventricular tachycardia, can lead to cardiac arrest and sudden death.
The findings are to be published in the January 16th issue of Circulation: Journal of the American Heart Association (news - web sites). Dr. Silvia G. Priori from the University of Pavia, Italy and associates report that the gene produces the RyR2 protein, which controls the release of calcium inside heart muscle cells. When RyR2 fails to function properly, calcium overload occurs, leading to rapid, irregular contractions of the heart that can result in death.
The researchers made the discovery by studying 12 youngsters and young adults who experienced fainting spells when they exercised or were under stress. Four of the 12 study participants had single mutations in the gene that resulted in alternations in the building blocks of the hRyR2 protein, the report indicates.
In one case, an 8-year-old had an identical twin brother who died suddenly at age 7 after a history of fainting spells. In another, a 30-year-old woman had two sisters that died in their teenage years. The woman developed heart palpitations and was given an implantable cardioverter defibrillator, a device that shocks the heart back into a normal rhythm when necessary. In the first year, the implant shocked her heart back into a normal rhythm two different times--once when she was in the process of being fired from her job and once when she was acting in a play.
The researchers tested 400 healthy people and none had mutations in the RyR2 genes.
``We demonstrated that mutations in RyR2 cause catecholaminergic ventricular tachycardia,'' the authors conclude.
``Finding the gene may help identify individuals at risk,'' Priori noted in a statement. Once identified, these individuals may be treated with drugs or devices, such as implantable defibrillators, to prevent the rapid heartbeat that causes sudden death.
SOURCE: Circulation January 16, 2001., http://www.100md.com
The condition, known catecholaminergic polymorphic ventricular tachycardia, can lead to cardiac arrest and sudden death.
The findings are to be published in the January 16th issue of Circulation: Journal of the American Heart Association (news - web sites). Dr. Silvia G. Priori from the University of Pavia, Italy and associates report that the gene produces the RyR2 protein, which controls the release of calcium inside heart muscle cells. When RyR2 fails to function properly, calcium overload occurs, leading to rapid, irregular contractions of the heart that can result in death.
The researchers made the discovery by studying 12 youngsters and young adults who experienced fainting spells when they exercised or were under stress. Four of the 12 study participants had single mutations in the gene that resulted in alternations in the building blocks of the hRyR2 protein, the report indicates.
In one case, an 8-year-old had an identical twin brother who died suddenly at age 7 after a history of fainting spells. In another, a 30-year-old woman had two sisters that died in their teenage years. The woman developed heart palpitations and was given an implantable cardioverter defibrillator, a device that shocks the heart back into a normal rhythm when necessary. In the first year, the implant shocked her heart back into a normal rhythm two different times--once when she was in the process of being fired from her job and once when she was acting in a play.
The researchers tested 400 healthy people and none had mutations in the RyR2 genes.
``We demonstrated that mutations in RyR2 cause catecholaminergic ventricular tachycardia,'' the authors conclude.
``Finding the gene may help identify individuals at risk,'' Priori noted in a statement. Once identified, these individuals may be treated with drugs or devices, such as implantable defibrillators, to prevent the rapid heartbeat that causes sudden death.
SOURCE: Circulation January 16, 2001., http://www.100md.com