Genome report: First whole genome sequence of Triatoma sanguisuga (Le Conte, 1855), vector of Chagas disease

G3 (Bethesda). 2024 Dec 31:jkae308. doi: 10.1093/g3journal/jkae308. Online ahead of print.

Abstract

Triatoma sanguisuga is the most widespread triatomine bug species in the United States (US). The species vectors the human parasite Trypanosoma cruzi, which causes Chagas disease. Vector-borne Chagas disease is rarely diagnosed in the US, but T. sanguisuga has been implicated in a handful of cases. Despite its public health importance, little is known about the genomics or population genetics of T. sanguisuga. Here, we used long-read sequencing to assemble the first whole genome sequence for T. sanguisuga using DNA extracted from one adult specimen from Delaware. The final size of the genome was 1.162 Gbp with 77.7x coverage. The assembly consisted of 183 contigs with an N50 size of 94.97 Kb. The Benchmarking Universal Single-Copy Ortholog (BUSCO) complete score was 99.1%, suggesting a very complete assembly. Genome-wide GC level was 33.56%, and DNA methylation was 18.84%. The genome consists of 62.75% repetitive DNA and 17,799 predicted coding genes. The assembled T. sanguisuga genome was very close in size and BUSCO score to that of Triatominae species Triatoma dimidiata (1.16 Gbp with 99.1% BUSCO score for T. sanguisuga vs 1.22 Gbp with 98.7% BUSCO score for T. dimidiata) and slightly larger than that of T. infestans and Rhodnius prolixus (949 Mbp with 90.4% BUSCO score and 706 Mbp with 96.5% BUSCO score, respectively). The T. sanguisuga genome is the first North American triatomine species genome to be sequenced, allowing for deeper investigations into epidemiologically relevant aspects of triatomines in temperate climates, thus providing potential vector-borne disease management targets and strengthening public health preparedness.

Keywords: Triatoma sanguisuga; Trypanosoma cruzi; Chagas disease; disease vectors; triatomine bugs.