The draft genome sequence of the Brahminy blindsnake Indotyphlops braminus

Abstract

Blindsnakes of infraoder Scolecophidia (order Squamata) are the most basal group of extant snakes, comprising of more than 450 species with ecological and morphological features highly specialized to underground living. The Brahminy blindsnake, Indotyphlops braminus, is the only known obligate parthenogenetic species of snakes. Although the origin of I. braminus is thought to be South Asia, this snake has attracted worldwide attention as an alien species, as it has been introduced to all continents except Antarctica. In this study, we present the first draft genome assembly and annotation of I. braminus. We generated approximately 480 Gbp of sequencing data and produced a draft genome with a total length of 1.86 Gbp and N50 scaffold size of 1.25 Mbp containing 89.3% of orthologs conserved in Sauropsida. We also identified 0.98 Gbp (52.82%) of repetitive genome sequences and a total of 23,560 protein-coding genes. The first draft genome of I. braminus will facilitate further study of snake evolution as well as help to understand the emergence mechanism of parthenogenetic vertebrates.

Polyploidization of Indotyphlops braminus: evidence from isoform-sequencing

“…Although its origin was speculated to be southern or eastern Asia, I. braminus is now identified as a globally invasive species. It has been documented in tropical and subtropical regions worldwide, except South America [ 1 , 4 , 5 ]. The species is predominantly located in provinces south of the Yangtze River in China [ 6 ].…”

“…As the only truly parthenogenetic vertebrates, reptiles provide critical insights into the persistence of sexual reproduction [ 11 , 12 ]. Furthermore, I. braminus is an allotriploid species, that results from hybridization [ 2 , 3 , 5 ]. Allopolyploids potentially benefit from heterosis, by harbouring multiple gene copies that can evolve new or varied functions, facilitating niche expansion and adaptation to environmental changes [ 13 ].…”

“…Elucidating the timing and mechanism of polyploidy in this snake species will yield insights crucial for future research into polyploid vertebrates. A recent publication presented I. braminus draft genome, which exhibited a total length of 1.86 Gbp and an N50 scaffold size of 1.25 Mbp, indicative of a potentially chimeric single haplotype [ 5 ]. Acquiring high-quality genomic or transcriptomic data is vital for advancing related research.…”