Megabase Length Hypermutation Accompanies Human Structural Variation at 17p11.2.

Authors: Beck, Christine R and Carvalho, Claudia M B and Akdemir, Zeynep C and Sedlazeck, Fritz J and Song, Xiaofei and Meng, Qingchang and Hu, Jianhong and Doddapaneni, Harsha and Chong, Zechen and Chen, Edward S and Thornton, Philip C and Liu, Pengfei and Yuan, Bo and Withers, Marjorie and Jhangiani, Shalini N and Kalra, Divya and Walker, Kimberly and English, Adam C and Han, Yi and Chen, Ken and Muzny, Donna M and Ira, Grzegorz and Shaw, Chad A and Gibbs, Richard A and Hastings, P J and Lupski, James R

DNA rearrangements resulting in human genome structural variants (SVs) are caused by diverse mutational mechanisms. We used long- and short-read sequencing technologies to investigate end products of de novo chromosome 17p11.2 rearrangements and query the molecular mechanisms underlying both recurrent and non-recurrent events. Evidence for an increased rate of clustered single-nucleotide variant (SNV) mutation in cis with non-recurrent rearrangements was found. Indel and SNV formation are associated with both copy-number gains and losses of 17p11.2, occur up to ~1 Mb away from the breakpoint junctions, and favor C > G transversion substitutions; results suggest that single-stranded DNA is formed during the genesis of the SV and provide compelling support for a microhomology-mediated break-induced replication (MMBIR) mechanism for SV formation. Our data show an additional mutational burden of MMBIR consisting of hypermutation confined to the locus and manifesting as SNVs and indels predominantly within genes. Copyright © 2019 Elsevier Inc. All rights reserved.

Journal: Cell
DOI: 10.1016/j.cell.2019.01.045
Year: 2019

Read publication