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Genotype phenotype analysis in a family carrying truncating mutations in the titin gene.

ABSTRACT: We report a family carrying a previously described truncating mutation, NM_001267550.2(TTN):c.107889del p.(Lys35963Asnfs*9) in exon 364, and a novel truncating mutation, NM_001267550.1:c.100704C > A p.(Tyr33568*) in exon 358 in the titin gene. The c.107889del mutation, which was maternally transmitted, has been previously described in patients from the Iberian Peninsula. The mother was of Peruvian descent suggesting a potential European ancestral origin of this mutation. In this family, a daughter, who is a compound heterozygote carrying both these mutations, developed a peripartum cardiomyopathy during her second pregnancy. Subsequently, she was diagnosed with a myopathy following electromyography testing and a muscle biopsy which showed fiber type disproportion. Her brother, who carries only the paternally inherited c.100704C > A mutation, developed a cardiomyopathy following a suspected viral illness. Their father, who transmitted this mutation, has no evidence of a cardiomyopathy. We hypothesize that the c.100704C > A mutation confers susceptibility to the development of cardiomyopathy which may be brought on by cardiovascular stress. Our study of this family expands the genotype and phenotype spectrum of disorders that can be associated with mutations in the titin gene.

SUBMITTER: Peddareddygari LR

PROVIDER: S-EPMC8033428 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Genotype phenotype analysis in a family carrying truncating mutations in the titin gene.

Peddareddygari Leema Reddy LR Baisre-de León Ada A Grewal Raji P RP

Acta myologica : myopathies and cardiomyopathies : official journal of the Mediterranean Society of Myology 20210331 1

We report a family carrying a previously described truncating mutation, NM_001267550.2(TTN):c.107889del p.(Lys35963Asnfs*9) in exon 364, and a novel truncating mutation, NM_001267550.1:c.100704C > A p.(Tyr33568*) in exon 358 in the <i>titin</i> gene. The c.107889del mutation, which was maternally transmitted, has been previously described in patients from the Iberian Peninsula. The mother was of Peruvian descent suggesting a potential European ancestral origin of this mutation. In this family, a ...[more]

PMID: 33870097

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Dataset Information

Genotype phenotype analysis in a family carrying truncating mutations in the titin gene.

Publications

Genotype phenotype analysis in a family carrying truncating mutations in the titin gene.

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