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bioRxiv · 10.64898/2026.06.11.731602

Chromosome-level genome assembly of the Northeast China Brown Frog (Rana dybowskii)

zhang, y.·Wang, D.·Zhao, R.·Li, S.·Zheng, X.·Hu, G.
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Abstract

Rana dybowskii is distributed across Northeast Asian and represents a valuable medical resource. A high-quality assembly of the genome has not yet been reproted. This species has 2n=24 chromosomes, but a huge genome size that estimated at 3.5 ~4.6 Gb in the previous studies. The relatively large chromosome size, exceeding hundreds of megabases, may result in difficulties of obtaining a complete chromosome level genome. Here, we constructed a chromosome-level genome assembly of R. dybowskii by integrating PacBio HiFi long-read sequencing for de novo assembly and CiFi (3C coupled with HiFi sequencing) for scaffolding. The final assembly consists of 12 chromosomes with a total of 3.95 Gb and a scaffold N50 length of 455 Mb. BUSCO assessment using the tetrapoda_odb12 database identified 94.2% complete and 0.5% fragmented orthologs, suggesting a high level of completeness of the assembly. Genomic annotation revealed that repetitive sequences comprise over 53% of the assembly, with retroelements and DNA transposons accounting for 22% and 25%, respectively. A total of 43,999 protein-coding genes were predicted with the assistance of RNA-seq reads from four tissues (muscle, eye, testis and skin). This high-quality chromosome-level reference genome provides a valuable genomic resource for advancing genetic studies of the species.

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zhang, y., Wang, D., Zhao, R., Li, S., Zheng, X., Hu, G.. 2026-06-15. Chromosome-level genome assembly of the Northeast China Brown Frog (Rana dybowskii). https://doi.org/10.64898/2026.06.11.731602

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