Low prevalence and variable clinical presentation of troponin I and troponin T gene mutations in hypertrophic cardiomyopathy.
Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disorder caused by mutations in cardiac sarcomeric proteins. Troponin I (TNNI3) and troponin T (TNNT2) are important parts of the sarcomere in heart muscle, and mutations in their genes are responsible for development of HCM. The prevalence of mutations in these two genes is low; hence, the data on clinical outcome are scarce. Yet, some of these mutations were shown to be malignant with a high incidence of sudden death. Here, we describe the disease course in three families affected with TNNI3 and one family with TNNT2 gene mutations. In TNNI3-HCM, the phenotypic manifestation ranged from clinically silent to sudden cardiac death with the worst prognosis observed in carriers of Ala157Val mutation in exon 7. In contrast, TNNT2-HCM was associated with favorable prognosis. Thus, the findings of the present study add evidence on the phenotypic presentation of this genetic disease.
Curila
Karol
K
Cardiocenter, Department of Cardiology, 3rd Faculty of Medicine, Charles University, and University Hospital Kralovske Vinohrady, Prague, Czech Republic. curila@fnkv.cz
Benesova
Lucie
L
Penicka
Martin
M
Minarik
Marek
M
Zemanek
David
D
Veselka
Josef
J
Widimsky
Petr
P
Gregor
Pavel
P
D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000235:genetics* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D019210:Troponin I / Q000235:genetics*; D020107:Troponin T / Q000235:genetics*
D019210:Troponin I; D020107:Troponin T