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Updated: Jun 11, 2026
14:57
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
Interpreting TP53 variants: somatic mosaicism and ERCC6L2-driven clonal evolution
Amalie Noergaard Andersson1, Anna Byrjalsen1, Ida Elisabeth Viller Tuxen2
1Department of Clinical Genetics, Rigshospitalet, Copenhagen, Denmark.
Journal of Medical Genetics
|June 9, 2026
Summary
Accurate interpretation of TP53 pathogenic variants (PVs) is crucial for cancer diagnosis and management. These cases demonstrate challenges in identifying TP53 PVs and underscore the need for careful clinical evaluation.
Area of Science:
- Genetics and Genomics
- Oncology
- Clinical Diagnostics
Background:
- TP53 pathogenic variants (PVs) are associated with various cancers and complex clinical presentations.
- Diagnostic challenges arise from mosaicism and distinguishing somatic from germline variants.
Purpose of the Study:
- To illustrate diagnostic, surveillance, and management complexities associated with TP53 PVs.
- To emphasize the importance of accurate TP53 variant interpretation in clinical decision-making.
Main Methods:
- Case report analysis of two patients with TP53 PVs.
- Review of diagnostic sequencing, variant allele frequency analysis, and clinical phenotyping.
Main Results:
- Case 1: A 24-year-old female with early-onset breast cancer and a missed somatic mosaic TP53 PV.
- Case 2: A 59-year-old female with multiple tumors, initially suspected mosaicism, later identified as a myelodysplastic syndrome-related clone secondary to ERCC6L2 variants.
Conclusions:
- Accurate interpretation of TP53 PVs is essential for appropriate diagnosis, treatment, and surveillance.
- Clinical context, including age, phenotype, family history, and tissue type, is vital for guiding TP53 variant assessment.
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