Pathogenic TERT promoter variants in telomere diseases.
Ontology highlight
ABSTRACT: Purpose
The acquisition of pathogenic variants in the TERT promoter (TERTp) region is a mechanism of tumorigenesis. In nonmalignant diseases, TERTp variants have been reported only in patients with idiopathic pulmonary fibrosis (IPF) due to germline variants in telomere biology genes.Methods
We screened patients with a broad spectrum of telomeropathies (n = 136), their relatives (n = 52), and controls (n = 195) for TERTp variants using a customized massively parallel amplicon-based sequencing assay.Results
Pathogenic -124 and -146 TERTp variants were identified in nine (7%) unrelated patients diagnosed with IPF (28%) or moderate aplastic anemia (4.6%); five of them also presented cirrhosis. Five (10%) relatives were also found with these variants, all harboring a pathogenic germline variant in telomere biology genes. TERTp clone selection did not associate with peripheral blood counts, telomere length, and response to danazol treatment. However, it was specific for patients with telomeropathies, more frequently co-occurring with TERT germline variants and associated with aging.Conclusion
We extend the spectrum of nonmalignant diseases associated with pathogenic TERTp variants to marrow failure and liver disease due to inherited telomerase deficiency. Specificity of pathogenic TERTp variants for telomerase dysfunction may help to assess the pathogenicity of unclear constitutional variants in the telomere diseases.
SUBMITTER: Gutierrez-Rodrigues F
PROVIDER: S-EPMC6555700 | biostudies-literature |
REPOSITORIES: biostudies-literature
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