[Study of mutations causing hypertrophic cardiomyopathy in a group of patients from Espirito Santo, Brazil].
BACKGROUND
Hypertrophic cardiomyopathy (HC) is the most frequent cardiac hereditary disease, caused by mutations in sarcomere protein coding genes. Although more than 430 mutations have been identified in several continents and countries, there have been no reports of mutations in Brazil.


OBJECTIVE
To carry out a genetic study to identify genetic mutations that cause HC in a group of patients in Espirito Santo, Brazil.


METHODS
Using the SSCP technique, 12 exons from the three main genes involved in HC were studied: exons 15, 20, 21, 22 and 23 of the beta-myosin heavy chain gene (MYH7), exons 7, 16, 18, 22 and 24 of the myosin binding protein C gene (MYBPC3) and exons 8 and 9 of troponin T gene (TNNT2).


RESULTS
16 alterations were found, including two mutations, one of them possibly pathogenic in the MYBPC3 gene (p. Glu441Lys) and another pathogenic one, previously described in the TNNT2 gene (p.Arg92Trp), 8 rare sequence variations and 6 sequence variations with allelic frequency higher than 1% (polymorphisms).


CONCLUSIONS
These data allow the conclusion that the genotyping of patients is feasible in our country. It is possible that the isolated p.Glu441Lys variant identified in exon 16 of the MYBPC3 gene is pathogenic, promoting a milder phenotype than that found when in association with other mutations. The p.Arg92Trp variant in the exon 9 of TNNT2 gene does not promote such a homogeneous phenotype as previously described and it can lead to severe hypertrophy.
Marsiglia
Júlia Daher Carneiro
JD
Universidade Federal do Espírito Santo, Vitória, ES, Brasil. marsigliajdc@yahoo.com.br
Batitucci
Maria do Carmo Pimentel
Mdo C
Paula
Flávia de
Fd
Barbirato
Clara
C
Arteaga
Edmundo
E
Araújo
Aloir Queiroz de
AQ
D001938:Brazil / Q000453:epidemiology; D002312:Cardiomyopathy, Hypertrophic / Q000453:epidemiology / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics; D016022:Case-Control Studies; D005091:Exons / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011110:Polymorphism, Genetic / Q000235:genetics*; D020107:Troponin T / Q000235:genetics*; D000099163:Myosin Binding Protein C
D002352:Carrier Proteins; D020107:Troponin T; D000099163:Myosin Binding Protein C; C545568:TNNT2 protein, human