[New paper] Analysis of low-level somatic mosaicism reveals stage- and tissue-specific mutational features in human development

Our new paper has been published in PLOS GENETICS.

In this paper, in collaboration with Prof. Jeong Ho Lee (KAIST), Dr. Ja Hye Kim and Shinwon Hwang performed a systemic and comprehensive analysis of low-level somatic mutations using deep whole-exome sequencing (average read depth ~500×) of 498 multiple organ tissues with matched controls from 190 individuals.  

Our results showed that early clone-forming mutations shared between multiple organs were lower in number but showed higher allele frequencies than late clone-forming mutations [0.54 vs. 5.83 variants per individual; 6.17% vs. 1.5% variant allele frequency (VAF)] along with less nonsynonymous mutations and lower functional impacts. Additionally, early and late clone-forming mutations had unique mutational signatures that were distinct from mutations that originated from tumors. Compared with early clone-forming mutations that showed a clock-like signature across all organs or tissues studied, late clone-forming mutations showed organ, tissue, and cell-type specificity in the mutation counts, VAFs, and mutational signatures. In particular, analysis of brain somatic mutations showed a bimodal occurrence and temporal-lobe-specific signature.

Congratulations!

PLoS Genet 18(9): e1010404. https://doi.org/10.1371/journal.pgen.1010404