Mutational screening of phospholamban gene in hypertrophic and idiopathic dilated cardiomyopathy and functional study of the PLN -42 C>G mutation.
BACKGROUND
Phospholamban is an endogenous sarcoplasmic reticulum calcium ATPase inhibitor with a regulatory effect on cardiac contraction/relaxation coupling. Mutations in the phospholamban gene (PLN) have been associated with primary cardiomyopathies.


OBJECTIVE
To screen for PLN mutations in our population of patients with primary cardiomyopathies and to perform functional analysis of the mutations identified.


METHODS
We performed SSCP mutational screening and DNA sequencing of the PLN gene in 186 patients with either hypertrophic or dilated cardiomyopathy. To study promoter strength we constructed reporter plasmids containing the luciferase gene and performed transient transfection analysis in C6 and C2C12 cell lines.


RESULTS
The PLN -42 C>G mutation was found in one patient with late onset familial apical hypertrophic cardiomyopathy. This mutation decreased phospholamban promoter activity by 43% and 47%, in C6 and C2C12 cell lines respectively. One son had mild apical hypertrophic cardiomyopathy and carried the mutation, another son with normal ECG and echocardiogram also had the mutation.


CONCLUSIONS
The PLN -42 C>G mutation is associated with a benign form of apical hypertrophic cardiomyopathy in this family, though the presence of a healthy adult carrier suggests that other genetic and environmental factors could be involved. Otherwise, mutations in the PLN gene are not a frequent cause of cardiomyopathies in our population.
Medin
Maria
M
Hospital Universitario Juan Canalejo, Spain.
Hermida-Prieto
Manuel
M
Monserrat
Lorenzo
L
Laredo
Rafael
R
Rodriguez-Rey
Jose Carlos
JC
Fernandez
Xustox
X
Castro-Beiras
Alfonso
A
D002135:Calcium-Binding Proteins / Q000235:genetics*; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging / Q000235:genetics*; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000235:genetics*; D002460:Cell Line; D003596:Cytosine; D004252:DNA Mutational Analysis; D004562:Electrocardiography; D006147:Guanine; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D018807:Polymorphism, Single-Stranded Conformational; D011401:Promoter Regions, Genetic; D014162:Transfection; D014463:Ultrasonography; D000099211:Phospholamban
D002135:Calcium-Binding Proteins; D003596:Cytosine; D006147:Guanine; D000099211:Phospholamban