Cardiac troponin T (TNNT2) mutations in Chinese dilated cardiomyopathy patients

Background. Dilated cardiomyopathy (DCM) is one of the leading causes of heart failure with high morbidity and mortality. Although more than 40 genes have been reported to cause DCM, the role of genetic testing in clinical practice is not well defined. Mutations in the troponin T (TNNT2) gene represent an important subset of known disease-causing mutations associated with DCM. Therefore, the aim of the present study was to determine the genetic variations in TNNT2 and the associations of those variations with DCM in Chinese patients. Methods. An approximately 4 kb fragment of the TNNT2 gene was isolated from 103 DCM patients and 192 healthy controls and was analyzed by DNA sequence analysis for genetic variations. Results. A total of 6 TNNT2 mutations were identified in 99 patients, including a G321T missense mutation (Leu84Phe) and 5 novel intronic mutations. Alleles of two novel SNPs (c. 192 + 353 C > A, OR = 0.095, 95% CI: 0.013 - 0.714, P = 0.022; c. 192 + 463 G > A, OR = 0.090, 95% CI: 0.012 - 0.675, P = 0.019) and SNP rs3729843 (OR = 1.889, 95% CI: 1.252 - 2.852; P = 0.002) were significantly correlated with DCM. Conclusions. These results suggest that the missense mutation (Leu84Phe) and two novel SNPs (c. 192 + 353 C > A, c. 192 + 463 G > A) in TNNT2 gene might be associated with DCM in the Chinese population.