BACKGROUND: The genetic background of catecholaminergic polymorphic ventricular tachycardia (CPVT) has been extensively investigated for the last decade in Western countries, but it remains unstudied in the Asian population. METHODS AND RESULTS: In 50 Japanese probands from unrelated families who satisfied clinical criteria for CPVT, genetic testing was conducted in all exons on 3 CPVT-related genes: cardiac ryanodine receptor 2 (RYR2), calsequestrin 2 (CASQ2) and inward rectifier potassium channel 2 (KCNJ2), and the clinical features between RYR2-genotyped and -non-genotyped patient groups were compared. Genetic and clinical evaluation was also done in 46 family members. In the genetic screening, 28 (18 novel) RYR2 (56.0%), 1 compound heterozygous CASQ2 (2.0%) and 1 KCNJ2 (2.0%) mutation carriers were identified. In the RYR2 mutation-positive group, the frequency of bidirectional ventricular tachycardia and the use of β-blockers were significantly higher than in the mutation-negative group. In contrast, there was no significant difference in supraventricular arrhythmias between the 2 groups. With regard to disease penetrance, the number of family members of RYR2-genotyped probands with a clinical diagnosis of CPVT was high. CONCLUSIONS: Thirty gene mutation carriers were found for 3 genes in 50 probands clinically diagnosed as having CPVT. The penetrance of CPVT phenotype was significantly higher in RYR2 mutation carriers, thus RYR2 gene screening in CPVT patients would be indispensable to prevent unexpected cardiac sudden death of young family members.
BACKGROUND: The genetic background of catecholaminergic polymorphic ventricular tachycardia (CPVT) has been extensively investigated for the last decade in Western countries, but it remains unstudied in the Asian population. METHODS AND RESULTS: In 50 Japanese probands from unrelated families who satisfied clinical criteria for CPVT, genetic testing was conducted in all exons on 3 CPVT-related genes: cardiac ryanodine receptor 2 (RYR2), calsequestrin 2 (CASQ2) and inward rectifier potassium channel 2 (KCNJ2), and the clinical features between RYR2-genotyped and -non-genotyped patient groups were compared. Genetic and clinical evaluation was also done in 46 family members. In the genetic screening, 28 (18 novel) RYR2 (56.0%), 1 compound heterozygous CASQ2 (2.0%) and 1 KCNJ2 (2.0%) mutation carriers were identified. In the RYR2 mutation-positive group, the frequency of bidirectional ventricular tachycardia and the use of β-blockers were significantly higher than in the mutation-negative group. In contrast, there was no significant difference in supraventricular arrhythmias between the 2 groups. With regard to disease penetrance, the number of family members of RYR2-genotyped probands with a clinical diagnosis of CPVT was high. CONCLUSIONS: Thirty gene mutation carriers were found for 3 genes in 50 probands clinically diagnosed as having CPVT. The penetrance of CPVT phenotype was significantly higher in RYR2 mutation carriers, thus RYR2 gene screening in CPVT patients would be indispensable to prevent unexpected cardiac sudden death of young family members.
Authors: Laurence M Nunn; Luis R Lopes; Petros Syrris; Cian Murphy; Vincent Plagnol; Eileen Firman; Chrysoula Dalageorgou; Esther Zorio; Diana Domingo; Victoria Murday; Iain Findlay; Alexis Duncan; Gerry Carr-White; Leema Robert; Teofila Bueser; Caroline Langman; Simon P Fynn; Martin Goddard; Anne White; Henning Bundgaard; Laura Ferrero-Miliani; Nigel Wheeldon; Simon K Suvarna; Aliceson O'Beirne; Martin D Lowe; William J McKenna; Perry M Elliott; Pier D Lambiase Journal: Europace Date: 2015-10-25 Impact factor: 5.214
Authors: Abdullah Omar; Mi Zhou; Adam Berman; Robert A Sorrentino; Neela Yar; Neal L Weintraub; Il-Man Kim; Wei Lei; Yaoliang Tang Journal: Expert Rev Precis Med Drug Dev Date: 2016-12-02