Molecular genetic analysis of PRKAG2 in sporadic Wolff-Parkinson-White syndrome.
BACKGROUND
Mutations in the PRKAG2 gene that encodes the gamma2 regulatory subunit of AMP-activated protein kinase have been shown to cause autosomal dominant Wolff-Parkinson-White (WPW) syndrome associated with hypertrophic cardiomyopathy. Prior studies focused on familial WPW syndrome associated with other heart disease such as hypertrophic cardiomyopathy. However, such disease accounts for only a small fraction of WPW cases, and the contribution of PRKAG2 mutations to sporadic isolated WPW syndrome is unknown.


RESULTS
Subjects presented for clinical electrophysiologic evaluation of suspected WPW syndrome. WPW syndrome was diagnosed by ECG findings and/or by clinically indicated electrophysiologic study prior to enrollment. Echocardiography excluded hypertrophic cardiomyopathy. Denaturing high-performance liquid chromatography and automated sequencing were used to search for PRKAG2 mutations. Twenty-six patients without a family history of WPW syndrome were studied. No subject had cardiac hypertrophy, and only one patient had associated congenital heart disease. Accessory pathways were detected at diverse locations within the heart. Two polymorphisms in PRKAG2 were detected. [inv6+36insA] occurred in intron 6 in 4 WPW patients and [inv10+10delT] in intron 10 in 1 WPW patient. Both occurred in normal unrelated chromosomes. No PRKAG2 mutations were detected.


CONCLUSIONS
This study shows that, unlike familial WPW syndrome, constitutional mutation of PRKAG2 is not commonly associated with sporadic WPW syndrome. Although polymorphisms within the PRKAG2 introns were identified, there is no evidence that these polymorphisms predispose to accessory pathway formation because their frequency is similarly high in both WPW patients and normal individuals. Further studies are warranted to identify the molecular basis of common sporadic WPW syndrome.
Vaughan
Carl J
CJ
Molecular Cardiology Laboratory, Department of Medicine, Weill Medical College of Cornell University, The New York-Presbyterian Hospital, New York, New York 10021, USA.
Hom
Yolanda
Y
Okin
Daniel A
DA
McDermott
Deborah A
DA
Lerman
Bruce B
BB
Basson
Craig T
CT
D055372:AMP-Activated Protein Kinases; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D007438:Introns; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000235:genetics*; D009154:Mutation; D011110:Polymorphism, Genetic; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D014927:Wolff-Parkinson-White Syndrome / Q000175:diagnosis / Q000235:genetics* / Q000628:therapy
D009097:Multienzyme Complexes; D017346:Protein Serine-Threonine Kinases; D055372:AMP-Activated Protein Kinases