Genetic Test for Long QT Syndrome Developed
Three-tiered strategy predicts syndrome in over 50% of patients
TUESDAY, Dec. 20 (HealthDay News) -- Researchers have developed a novel and efficient genetic testing method for long QT syndrome (LQTS) that may improve treatment for patients, as well as reduce cost and make genetic testing more widely available, according to a study in the Dec. 21 issue of the Journal of the American Medical Association.
Carlo Napolitano, M.D., Ph.D., of the University of Pavia in Italy, and colleagues screened 430 patients for mutations in one of five genes associated with a long QT disease called Romano-Ward syndrome. A three-tiered testing strategy was developed that was validated in an additional 75 affected individuals.
The authors found 235 different mutations in 310 patients, 138 of which were unique, and most of which were found in two of the five Romano-Ward associated genes. Fifty-eight percent of patients carry what the authors call "nonprivate mutations," or mutations found in more than one patient, in 64 amino acid coding sequences.
"The novel strategy for LQTS genotyping may facilitate the access to genetic testing to a broader group of individuals, such as patients receiving drugs that... prolong QT interval; family members of individuals with idiopathic ventricular fibrillation; and depending on results of further investigation, members of the general population to define the prevalence of known genetic variants of LQTS," the authors write.