Browsing by Author "Korbel, Jan O."

Now showing 1 - 3 of 3
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    Impact and characterization of serial structural variations across humans and great apes
    (Springer Nature, 2024) Höps, Wolfram; Rausch, Tobias; Jendrusch, Michael; Korbel, Jan O.; Sedlazeck, Fritz J.
    Modern sequencing technology enables the systematic detection of complex structural variation (SV) across genomes. However, extensive DNA rearrangements arising through a series of mutations, a phenomenon we refer to as serial SV (sSV), remain underexplored, posing a challenge for SV discovery. Here, we present NAHRwhals (https://github.com/WHops/NAHRwhals), a method to infer repeat-mediated series of SVs in long-read genomic assemblies. Applying NAHRwhals to haplotype-resolved human genomes from 28 individuals reveals 37 sSV loci of various length and complexity. These sSVs explain otherwise cryptic variation in medically relevant regions such as the TPSAB1 gene, 8p23.1, 22q11 and Sotos syndrome regions. Comparisons with great ape assemblies indicate that most human sSVs formed recently, after the human-ape split, and involved non-repeat-mediated processes in addition to non-allelic homologous recombination. NAHRwhals reliably discovers and characterizes sSVs at scale and independent of species, uncovering their genomic abundance and suggesting broader implications for disease.
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    Inverted triplications formed by iterative template switches generate structural variant diversity at genomic disorder loci
    (Elsevier, 2024) Grochowski, Christopher M.; Bengtsson, Jesse D.; Du, Haowei; Gandhi, Mira; Lun, Ming Yin; Mehaffey, Michele G.; Park, KyungHee; Höps, Wolfram; Benito, Eva; Hasenfeld, Patrick; Korbel, Jan O.; Mahmoud, Medhat; Paulin, Luis F.; Jhangiani, Shalini N.; Hwang, James Paul; Bhamidipati, Sravya V.; Muzny, Donna M.; Fatih, Jawid M.; Gibbs, Richard A.; Pendleton, Matthew; Harrington, Eoghan; Juul, Sissel; Lindstrand, Anna; Sedlazeck, Fritz J.; Pehlivan, Davut; Lupski, James R.; Carvalho, Claudia M. B.
    The duplication-triplication/inverted-duplication (DUP-TRP/INV-DUP) structure is a complex genomic rearrangement (CGR). Although it has been identified as an important pathogenic DNA mutation signature in genomic disorders and cancer genomes, its architecture remains unresolved. Here, we studied the genomic architecture of DUP-TRP/INV-DUP by investigating the DNA of 24 patients identified by array comparative genomic hybridization (aCGH) on whom we found evidence for the existence of 4 out of 4 predicted structural variant (SV) haplotypes. Using a combination of short-read genome sequencing (GS), long-read GS, optical genome mapping, and single-cell DNA template strand sequencing (strand-seq), the haplotype structure was resolved in 18 samples. The point of template switching in 4 samples was shown to be a segment of ∼2.2–5.5 kb of 100% nucleotide similarity within inverted repeat pairs. These data provide experimental evidence that inverted low-copy repeats act as recombinant substrates. This type of CGR can result in multiple conformers generating diverse SV haplotypes in susceptible dosage-sensitive loci.
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    Somatic structural variant formation is guided by and influences genome architecture
    (Cold Spring Harbor Laboratory Press, 2022) Sidiropoulos, Nikos; Mardin, Balca R.; Rodríguez-González, F. Germán; Bochkov, Ivan D.; Garg, Shilpa; Stütz, Adrian M.; Korbel, Jan O.; Aiden, Erez Lieberman; Weischenfeldt, Joachim; Center for Theoretical Biological Physics
    The occurrence and formation of genomic structural variants (SVs) is known to be influenced by the 3D chromatin architecture, but the extent and magnitude have been challenging to study. Here, we apply Hi-C to study chromatin organization before and after induction of chromothripsis in human cells. We use Hi-C to manually assemble the derivative chromosomes following the occurrence of massive complex rearrangements, which allows us to study the sources of SV formation and their consequences on gene regulation. We observe an action–reaction interplay whereby the 3D chromatin architecture directly impacts the location and formation of SVs. In turn, the SVs reshape the chromatin organization to alter the local topologies, replication timing, and gene regulation in cis. We show that SVs have a strong tendency to occur between similar chromatin compartments and replication timing regions. Moreover, we find that SVs frequently occur at 3D loop anchors, that SVs can cause a switch in chromatin compartments and replication timing, and that this is a major source of SV-mediated effects on nearby gene expression changes. Finally, we provide evidence for a general mechanistic bias of the 3D chromatin on SV occurrence using data from more than 2700 patient-derived cancer genomes.