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bioRxiv · 10.1101/2025.11.11.687924

Tick Genome Assemblies: Overcoming biological limitations through advances in sequencing and assembly

Dillon, K. C.·Frederick, J. C.·Sprong, H.·Glenn, T. C.·Ronai, I.
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Abstract

Ticks are blood-feeding arthropods with approximately 1,000 species, however, only 24 species currently have a genome assembly. These genome assemblies are important resources to advance tick biology and control of tick-associated diseases. Generating tick genome assemblies is challenging due to their small body size (low DNA input), DNA contamination (from microbiota and host bloodmeals), large genome size (on average 2.4 Gbp for hard ticks), and abundant transposable elements (at least 68% of the assembly for Ixodes species). Advances in sequencing technologies have driven an increasing number of tick assemblies from 2011 to 2025. We characterize and assess the 54 tick genome assemblies within public genome databases using QUAST-LG and BUSCO compleasm. Then we evaluate the impact of biological source material and sequencing platforms on these tick genome assemblies. From the 54 tick assemblies, we identify 34 high-quality assemblies from 21 species that are suitable for downstream analyses. We recommend future tick genome assemblies use long-read sequencing platforms and Hi-C scaffolding to improve genomic resources for these unique blood-feeding parasites.

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Dillon, K. C., Frederick, J. C., Sprong, H., Glenn, T. C., Ronai, I.. 2025-11-12. Tick Genome Assemblies: Overcoming biological limitations through advances in sequencing and assembly. https://doi.org/10.1101/2025.11.11.687924

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