Biology subjects

Hauenstein, J.

Publications and source records attributed to Hauenstein, J..

6 recordsLinked to original sources

bioRxiv2025

Comparative analysis of whole genome amplification kits for single cell genome analysis

Whole genome amplification (WGA) enables detailed analysis of genomic heterogeneity at the cellular level. Here, we systematically compare two commercially available WGA technologies on single cells; Multiple Displacement Amplification in the Qiagen REPLI-g kit (MDA/REPLI-g) and Primary Template-directed Amplification in the BioSkryb ResolveDNA kit (PTA/ResolveDNA). Beyond quality control and genomic profiling, we assessed a cost-effective array-based approach as a complement to low-pass sequencing. Consistent with available benchmarks, PTA/ResolveDNA sequencing libraries consistently outperformed MDA/REPLI-g across quality metrics, including genome coverage breadth and uniformity. CNV calls from PTA-cells showed higher accuracy and sensitivity, including reliable detection of small CNVs at low sequencing depth. SNP array-based analysis corroborated sequencing-based findings, and additionally provided allelic information. Notably, CNV detection from SNP arrays matched the performance of low-pass sequencing, supporting its utility as an cost-effective approach for WGA quality control and single-cell CNV profiling.

genomics↗

bioRxiv2025

Whole genome sequencing with AVITI and NovaSeq X Plus reveals comparable performance with contextual biases

Element Biosciences avidity sequencing has emerged as a competing technology to Illuminas short read sequencing platform. Prior benchmarks of avidity sequencing have not included the latest Illumina NovaSeq X/X Plus instruments with XLEAP chemistry. Here, we have run PCR-free whole genome sequencing on four human tumor cell lines using both Illumina NovaSeq X Plus and Element AVITI instruments. AVITI showed low duplication rates and reported higher base qualities, the latter contributed to improved mapping confidence and fewer spurious variant candidates. Both platforms were found to be highly comparable when benchmarking variant calling, with AVITI only providing a minor improvement on INDELs at lower coverages. Stratifying by genomic context revealed further differences, where AVITI genome coverage and variant calls were superior in high GC regions while being inferior in GC homopolymers. Error rate analysis highlighted further differences between the platforms, in particular AVITI in some instances displayed an increased error rate on read 2 related to short fragments. AVITI error rate was also found to be more stable downstream of repetitive regions, except for GC homopolymers. We further found that AVITI sequencing was sensitive to G-quadruplex motifs. Overall, despite these identified differences, both platforms performed highly comparable for variant analysis.

genomics↗

bioRxiv2023

Aging is associated with functional and molecular changes in distinct hematopoietic stem cell subsets

Age is a risk factor for hematologic malignancies. Attributes of the aging hematopoietic system include increased myelopoiesis, impaired adaptive immunity, and a functional decline of the hematopoietic stem cells (HSCs) that maintain hematopoiesis. Changes in the composition of diverse HSC subsets have been suggested to be responsible for age-related alterations, however, the underlying regulatory mechanisms are incompletely understood in the context of HSC heterogeneity. In this study, we investigated how distinct HSC subsets, separated by CD49b, functionally and molecularly change their behavior with age. We demonstrate that blood lineage differentiation progressively shifts to a higher myeloid cellular output in both lymphoid-biased and myeloid-biased HSC subsets during aging. In parallel, we show that HSCs selectively undergo age-dependent gene expression and gene regulatory molecular changes in a progressive manner, which is initiated already in the pre-adult stage. Overall, our studies suggest that aging intrinsically alters both cellular and molecular properties of HSCs. HighlightsO_LIWith age a gradual shift towards myeloid differentiation occurs in both myeloid-biased and lymphoid-biased enriched HSC subsets. C_LIO_LIAge-related molecular changes preferentially occur in HSCs. C_LIO_LIFunctionally distinct HSC subsets with high transcriptional similarity can be distinguished on the epigenetic level. C_LIO_LIHSC aging is associated with a progressive increase in chromatin accessibility. C_LI

cell biology↗

bioRxiv2022

T-RHEX-RNAseq - A tagmentation-based, rRNA blocked, random hexamer primed RNAseq method for generating stranded RNAseq libraries directly from very low numbers of lysed cells.

BackgroundRNA sequencing has become the mainstay for studies of gene expression. Still, analysis of rare cells with random hexamer priming - to allow analysis of a broader range of transcripts - remains challenging. ResultsWe here describe a tagmentation-based, rRNA blocked, random hexamer primed RNAseq approach (T-RHEX-RNAseq) for generating stranded RNAseq libraries from very low numbers of FACS sorted cells without RNA purification steps. ConclusionT-RHEX-RNAseq provides an easy-to-use, time efficient and automation compatible method for generating stranded RNAseq libraries from rare cells.

molecular biology↗

bioRxiv2022

FOXO dictates initiation of B cell development and myeloid restriction in common lymphoid progenitors

The development of B cells relies on an intricate network of transcription factors critical for developmental progression and lineage commitment. In the B cell developmental trajectory, a temporal switch from predominant Foxo3 to Foxo1 expression occurs at the CLP stage. Utilizing VAV-iCre mediated conditional deletion, we found that the loss of FOXO3 impaired B cell development from LMPP down to B cell precursors, while the loss of FOXO1 impaired B cell commitment and resulted in a complete developmental block at the CD25 negative proB cell stage. Strikingly, the combined loss of FOXO1 and FOXO3 resulted in the failure to restrict the myeloid potential of CLPs and the complete loss of the B cell lineage. This is underpinned by the failure to enforce the early B-lineage gene regulatory circuitry upon a predominantly pre-established open chromatin landscape. Altogether, this demonstrates that FOXO3 and FOXO1 cooperatively govern early lineage restriction and initiation of B-lineage commitment in CLPs. SUMMARYCommon lymphoid progenitors co-express the transcription factors FOXO1 and FOXO3. Removing FOXO1 and FOXO3 at this developmental stage results in regained myeloid potential, failed establishment of the early B cell gene regulatory program, and the complete loss of the B cell lineage.

immunology↗

bioRxiv2021

Linked-read whole-genome sequencing resolves common and private structural variants in multiple myeloma

Multiple myeloma (MM) is an incurable and aggressive plasma cell malignancy characterized by a complex karyotype with multiple structural variants (SVs) and copy number variations (CNVs). Linked-read whole-genome sequencing (lrWGS) allows for refined detection and reconstruction of SVs by providing long-range genetic information from standard short-read sequencing. This makes lrWGS an attractive solution for capturing the full genomic complexity of MM. Here we show that high-quality lrWGS data can be generated from low numbers of FACS sorted cells without DNA purification. Using this protocol, we analyzed FACS sorted MM cells from 37 MM patients with lrWGS. We found high concordance between lrWGS and FISH for the detection of recurrent translocations and CNVs. Outside of the regions investigated by FISH, we identified >150 additional SVs and CNVs across the cohort. Analysis of the lrWGS data allowed for resolving the structure of diverse SVs affecting the MYC and t(11;14) loci causing the duplication of genes and gene regulatory elements. In addition, we identified private SVs causing the dysregulation of genes recurrently involved in translocations with the IGH locus and show that these can alter the molecular classification of the MM. Overall, we conclude that lrWGS allows for the detection of aberrations critical for MM prognostics and provides a feasible route for providing comprehensive genetics. Implementing lrWGS could provide more accurate clinical prognostics, facilitate genomic medicine initiatives, and greatly improve the stratification of patients included in clinical trials. KEY POINTS- Linked-read WGS can be performed without DNA purification and allows for resolving the diverse structural variants found in multiple myeloma. - Linked-read WGS can, as a stand-alone assay, provide comprehensive genetics in myeloma and other diseases with complex genomes.

genetics↗