Somatic mosaics in hereditary tumor predisposition syndromes

Area of Science:

• Genetics
• Oncology
• Molecular Biology

Background:

• Germline cancer predisposition variants affect 5-10% of cancer patients, guiding clinical management.
• Mosaic variants, present in specific tissues, can alter or mask tumor predisposition syndrome phenotypes.
• Low-level parental mosaicism accounts for a significant proportion of presumed de novo variants.

Purpose of the Study:

• To highlight the prevalence and clinical significance of mosaic tumor predisposition syndromes.
• To discuss the diagnostic challenges and strategies for identifying mosaic variants.
• To present clinical cases illustrating mosaic tumor predisposition syndromes.

Main Methods:

• Review of existing literature on tumor predisposition syndromes and mosaicism.
• Analysis of variant allele frequencies and detection limits for different genetic testing technologies.
• Case study presentations of patients with mosaic tumor predisposition syndromes.

Main Results:

• Mosaic tumor predisposition syndromes are more prevalent than previously estimated and frequently undiagnosed.
• Mosaic variants can be challenging to detect using standard genetic testing in blood.
• Next-generation sequencing and array-based technologies can detect low-frequency mosaic variants.

Conclusions:

• Increased clinical suspicion and advanced diagnostic techniques are crucial for identifying mosaic tumor predisposition syndromes.
• Understanding mosaicism is essential for accurate genetic diagnostics and patient management.
• Early detection of mosaic tumor predisposition syndromes enables timely, tailored interventions.