Role of genetic analysis in the management of patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a recognized cause of sudden cardiac death, which may be prevented by timely detection and intervention. Clinical diagnosis of ARVC is fraught with difficulties in both index cases and relatives owing to the nonspecific nature of associated features, diverse phenotypic manifestations, and a lack of conspicuous abnormalities in the early, "concealed" phase. During the past 7 years, researchers have isolated causative mutations in several components of the desmosome, shedding light on the molecular mechanisms underlying the disease and offering the promise of genetic testing as a diagnostic tool. Sequence analysis is likely to be the mainstay of genotyping in ARVC because of marked allelic heterogeneity, frequent "private" mutations, and digenicity in a minority, highlighting the importance of comprehensive genetic screening. The main technical obstacle to implementation of genotyping in clinical practice will be the prohibitive costs of performing sequence analysis of a genomic region exceeding 40 kb. Nevertheless, the success rate of genotyping in ARVC is of the order of 40%, and key clinical applications include confirmatory testing of index cases to facilitate interpretation of borderline investigations and cascade screening of families. The latter is particularly attractive in ARVC, because age-related penetrance otherwise demands lifelong clinical reassessment of extended families. A role for genetic analysis in prognostication is more tenuous at present, but increasing identification of individuals with early and familial disease underscores the need for a definitive risk stratification algorithm in this population.
Sen-Chowdhry
Srijita
S
Cardiology in the Young, The Heart Hospital, University College London, London, United Kingdom.
Syrris
Petros
P
McKenna
William J
WJ
D000367:Age Factors; D000483:Alleles; D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000175:diagnosis / Q000191:economics / Q000235:genetics* / Q000628:therapy; D002874:Chromosome Mapping / Q000191:economics; D003362:Cost-Benefit Analysis; D004252:DNA Mutational Analysis / Q000191:economics; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control; D017147:Defibrillators, Implantable / Q000191:economics; D051187:Desmocollins / Q000235:genetics; D051301:Desmoglein 2 / Q000235:genetics; D051180:Desmoplakins / Q000235:genetics; D018703:Founder Effect; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005820:Genetic Testing / Q000191:economics; D005838:Genotype; D006801:Humans; D008019:Life Style; D019683:Penetrance; D010641:Phenotype; D051191:Plakophilins / Q000235:genetics; D011379:Prognosis; D019837:Ryanodine Receptor Calcium Release Channel / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000191:economics; D053782:Transforming Growth Factor beta3 / Q000235:genetics; D051185:gamma Catenin
C081561:DSC2 protein, human; C495314:DSG2 protein, human; C495294:DSP protein, human; D051187:Desmocollins; D051301:Desmoglein 2; D051180:Desmoplakins; C495292:JUP protein, human; C495337:PKP2 protein, human; D051191:Plakophilins; D019837:Ryanodine Receptor Calcium Release Channel; D053782:Transforming Growth Factor beta3; D051185:gamma Catenin