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Mueller, F.-J.

Publications and source records attributed to Mueller, F.-J..

3 recordsLinked to original sources

The Greenland shark (Somniosus microcephalus) genome provides insights into extremelongevity

The Greenland shark (Somniosus microcephalus) is the longest-lived vertebrate known, with an estimated lifespan of [~] 400 years. Here, we present a chromosome-level assembly of the 6.45 Gb Greenland shark, rendering it one of the largest non-tetrapod genomes sequenced so far. Expansion of the genome is mostly accounted for by a substantial expansion of transposable elements. Using public shark genomes as a comparison, we found that genes specifically duplicated in the Greenland shark form a functionally connected network enriched for DNA repair function. Furthermore, we identified a unique insertion in the conserved C-terminal region of the key tumor suppressor p53. We also provide a public browser to explore its genome.

genomics↗

Chromosome-level genome assembly of the functionally extinct northern white rhinoceros (Ceratotherium simum cottoni).

The northern white rhinoceros (NWR; Ceratotherium simum cottoni) is functionally extinct, with only two females remaining alive. Efforts to rescue the NWR have inspired the exploration of unconventional conservation methods, including the generation of artificial gametes from induced pluripotent stem cells and somatic cell nuclear transfer. To enable the technologies required for these approaches, we used complementary sequencing and mapping methods to generate a NWR chromosome-level reference genome that meets or exceeds the metrics proposed by the Vertebrate Genome Project. It represents 40 autosomes, an X and a partially-resolved Y chromosome, and the mitochondrial genome. We compared the NWR reference genome to the southern white rhinoceros (SWR) population that has been physically separated from the NWR for tens of thousands of years. Using short-read data from the SWR and optical mapping, we found that the two populations are very similar on both the chromosome level and mitochondrial genome level. The results of this study are encouraging for the efforts underway to rescue the NWR.

genomics↗

Repeat expansion and methylation state analysis with nanopore sequencing

Expansions of short tandem repeats are genetic variants that have been implicated in neuropsychiatric and other disorders but their assessment remains challenging with current molecular methods. Here, we developed a Cas12a-based enrichment strategy for nanopore sequencing that, combined with a new algorithm for raw signal analysis, enables us to efficiently target, sequence and precisely quantify repeat numbers as well as their DNA methylation status. Taking advantage of these single molecule nanopore signals provides therefore unprecedented opportunities to study pathological repeat expansions.

genetics↗