Linkage Study of Long QT Syndrome In An Amish Kindred

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00005250
Recruitment Status : Completed
First Posted : May 26, 2000
Last Update Posted : May 13, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
To screen by electrocardiography the entire population of 1,400 individuals in seven Amish Mennonite communities in order to perform genetic linkage studies of long QT syndrome (LQTS).

Condition or disease
Heart Diseases Cardiovascular Diseases Tachycardia, Ventricular Ventricular Fibrillation Long QT Syndrome

Detailed Description:


LQTS is a severe heart disorder leading to sudden death due to ventricular tachycardia or ventricular fibrillation. The syndrome segregated as a Mendelian recessive in the highly inbred population under study and resulted in the sudden death of several members of the population.


The entire population was screened to identify cases of LQTS. In addition, 29 obligate heterozygotes were studied by 24-hour Holter monitoring to determine whether these gene carriers had any subtle phenotypes. The data were subjected to complex segregation and linkage analysis to establish the mode of inheritance and penetrance of LQTS.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

Study Type : Observational
Study Start Date : January 1990
Actual Study Completion Date : December 1992

Information from the National Library of Medicine

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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria Identifier: NCT00005250     History of Changes
Other Study ID Numbers: 1132
R01HL041035 ( U.S. NIH Grant/Contract )
First Posted: May 26, 2000    Key Record Dates
Last Update Posted: May 13, 2016
Last Verified: November 2001

Additional relevant MeSH terms:
Long QT Syndrome
Cardiovascular Diseases
Heart Diseases
Ventricular Fibrillation
Tachycardia, Ventricular
Pathologic Processes
Arrhythmias, Cardiac
Heart Defects, Congenital
Cardiovascular Abnormalities
Congenital Abnormalities