Lab Med Online.  2023 Oct;13(4):282-289. 10.47429/lmo.2023.13.4.282.

Detection of Mosaic Sequence Variants Associated with Human Genetic Diseases

• Kim MJ
• Lee JS
• Seong MW

• KMID: 2552754
• DOI: http://doi.org/10.47429/lmo.2023.13.4.282

Abstract

Mosaicism refers to cells with different genetic makeups within a single zygote. Although relatively common, the frequency of mosaicism is often underestimated, particularly in low-grade cases, due to limitations in detection methods. This review focuses on mosaicism and various detection techniques, emphasizing the types of specimens and tissues involved. While next-generation sequencing is a highly effective detection method, other techniques are expected to play a significant role in the identification or confirmation of mosaicism.

Keyword

Mosaicism; Germline; Somatic; Next-generation sequencing

Figure

• 

  Fig. 1 Distribution of mutant cells in the human body and different types of mosaicism in particular individuals. In somatic or germline mosaicism, mutant cells may appear with different mosaicism ratios in distinct tissues of patients, including gonads. (A) Example of somatic mosaicism confined to endoderm among the three germinal cell layers. (B) In focal cortical dysplasia, somatic mosaicism appears localized to a specific organ, such as the brain. (C) Germline or gonadal mosaicism refers to genetic variation in the genomes of germline cells within an individual. (D) Somatic and germline mosaicism may coexist in the same individual.

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