Genomic structural variants (SVs) contribute substantially to genetic diversity and human diseases^1–4, yet remain under-characterized in population-scale cohorts⁵. Here we conducted long-read sequencing⁶ in 1,019 humans to construct an intermediate-coverage resource covering 26 populations from the 1000 Genomes Project. Integrating linear and graph genome-based analyses, we uncover over 100,000 sequence-resolved biallelic SVs and we genotype 300,000 multiallelic variable number of tandem repeats⁷, advancing SV characterization over short-read-based population-scale surveys^3,4. We characterize deletions, duplications, insertions and inversions in distinct populations. Long interspersed nuclear element-1 (L1) and SINE-VNTR-Alu (SVA) retrotransposition activities mediate the transduction^8,9 of unique sequence stretches in 5′ or 3′, depending on source mobile element class and locus. SV breakpoint analyses point to a spectrum of homology-mediated processes contributing to SV formation and recurrent deletion events. Our open-access resource underscores the value of long-read sequencing in advancing SV characterization and enables guiding variant prioritization in patient genomes.

Structural variants (SVs) contribute significantly to human genetic diversity and disease ^1–4 . Previously, SVs have remained incompletely resolved by population genomics, with short-read sequencing facing limitations in capturing the whole spectrum of SVs at nucleotide resolution ^5–7 . Here we leveraged nanopore sequencing ⁸ to construct an intermediate coverage resource of 1,019 long-read genomes sampled within 26 human populations from the 1000 Genomes Project. By integrating linear and graph-based approaches for SV analysis via pangenome graph-augmentation, we uncover 167,291 sequence-resolved SVs in these samples, considerably advancing SV characterization compared to population-wide short-read sequencing studies ^3,4 . Our analysis details diverse SV classes—deletions, duplications, insertions, and inversions—at population-scale. LINE-1 and SVA retrotransposition activities frequently mediate transductions ^9,10 of unique sequences, with both mobile element classes transducing sequences at either the 3′- or 5′-end, depending on the source element locus. Furthermore, analyses of SV breakpoint junctions suggest a continuum of homology-mediated rearrangement processes are integral to SV formation, and highlight evidence for SV recurrence involving repeat sequences. Our open-access dataset underscores the transformative impact of long-read sequencing in advancing the characterisation of polymorphic genomic architectures, and provides a resource for guiding variant prioritisation in future long-read sequencing-based disease studies.

Currently, little is known about the genetic background of restrictive cardiomyopathy (RCM). Herein, we screened an index patient with RCM in combination with atrial fibrillation using a next generation sequencing (NGS) approach and identified the heterozygous mutation DES-c.735G>C. As DES-c.735G>C affects the last base pair of exon-3, it is unknown whether putative missense or splice site mutations are caused. Therefore, we applied nanopore amplicon sequencing revealing the expression of a transcript without exon-3 in the explanted myocardial tissue of the index patient. Western blot analysis verified this finding at the protein level. In addition, we performed cell culture experiments revealing an abnormal cytoplasmic aggregation of the truncated desmin form (p.D214-E245del) but not of the missense variant (p.E245D). In conclusion, we show that DES-c.735G>C causes a splicing defect leading to exon-3 skipping of the DES gene. DES-c.735G>C can be classified as a pathogenic mutation associated with RCM and atrial fibrillation. In the future, this finding might have relevance for the genetic understanding of similar cases.

Three novel corynebacterial species were isolated from soil sampled at a paddock in Vilsendorf, North Rhine-Westphalia, Germany. The strains were coccoid or irregular rod-shaped, catalase-positive and pale white to yellow-orange in colour. By whole genome sequencing and comparison of the 16S rRNA genes as well as the whole genome structure, it was shown that all three strains represent novel species of the family Corynebacteriaceae , order Corynebacteriales , class Actinobacteria . This project describes the isolation, identification, sequencing, and phenotypic characterization of the three novel Corynebacterium species. We propose the names Corynebacterium kalinowskii sp. nov. (DSM 110639T=LMG 31801T), Corynebacterium comes sp. nov. (DSM 110640T=LMG 31802T), and Corynebacterium occultum sp. nov. (DSM 110642T=LMG 31803T).

Mycosis fungoides (MF) is the most common cutaneous T-cell lymphoma (CTCL). At present, knowledge of genetic changes in early-stage MF is insufficient. Additionally, low tumor cell fraction renders calling of copy-number variations as the predominant mutations in MF challenging, thereby impeding further investigations. We show that enrichment of T cells from a biopsy of a stage I MF patient greatly increases tumor fraction. This improvement enables accurate calling of recurrent MF copy-number variants such as ARID1A and CDKN2A deletion and STAT5 amplification, undetected in the unprocessed biopsy. Furthermore, we demonstrate that application of long-read nanopore sequencing is especially useful for the structural variant rich CTCL. We detect the structural variants underlying recurrent MF copy-number variants and show phasing of multiple breakpoints into complex structural variant haplotypes. Additionally, we record multiple occurrences of templated insertion structural variants in this sample. Taken together, this study suggests a workflow to make the early stages of MF accessible for genetic analysis, and indicates long-read sequencing as a major tool for genetic analysis for MF.

Mycosis fungoides (MF), the most common form of cutaneous T-cell lymphoma, poses significant diagnostic challenges due to its overlap with benign inflammatory skin diseases and the absence of specific symptoms. Accurate early diagnosis and stratification of patients by progression risk are essential for effective treatment. This study proposes a proof-of-concept for integrating T-cell receptor (TCR) clonality analysis with somatic mutation profiling to enhance diagnostic confidence and prognostic accuracy in early-stage MF. This study’s methodology comprised the analysis of nine patients with early MF (stages IA/IB) using whole-exome sequencing and TCR repertoire profiling. The analysis revealed the presence of clonal TCR rearrangements in seven patients, while somatic mutations were identified in two. A notable finding was a recurrent chromosome 7 trisomy in these two cases. The patients were stratified into three molecular profiles: (1) somatic mutations with clonal TCR rearrangement (n = 2), (2) clonal TCR rearrangement without somatic mutations (n = 4), and (3) neither somatic mutations nor clonal TCR rearrangement (n = 3). These findings emphasise the heterogeneity of MF and underscore the limitations of relying solely on TCR clonality or mutation burden for diagnosis. This study underscores the potential of somatic mutations as diagnostic markers to distinguish MF from benign conditions and as prognostic indicators for disease progression. A combined genetic approach may refine treatment decisions, particularly for patients with higher tumor cell fractions and pronounced genetic alterations. Despite the limited size of the cohort, the results advocate for larger, multi-center studies to validate these findings and integrate genetic analyses into routine MF management.