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Bellinger, M. R.

Publications and source records attributed to Bellinger, M. R..

2 recordsLinked to original sources

Genomic Structural Variation Rescues a Classic Biological Invader from a Population Bottleneck

Invasion genetics presents a classic paradox: how do species successfully spread despite severe population bottlenecks? The brown treesnake (Boiga irregularis) in Guam represents a striking example of this phenomenon, having been introduced with only a handful of individuals. We show that the population endured an extreme bottleneck, with roughly half of the genome exhibiting runs of homozygosity, comparable to species of conservation concern. Despite this, we uncovered extensive diversity in the form of nearly 19,000 genomic structural variants, which affect almost eight times more of the genome than single-nucleotide variants and provide material for rescuing the population from inbreeding-driven declines. Structural variant density was highest in gene promoters, where recombination and DNA repair often occur, providing a mechanism for rapid evolution of gene-linked diversity. This diversity is enriched in genes vital for adaptive immunity and olfaction, suggesting genomic diversity in key chromosomal regions can rescue populations from inbreeding. This work has critical implications for invasion biology and conservation genetics practitioners. TEASERGenomic structural variants rescue a textbook biological invader from a population bottleneck and inbreeding

genomics↗

A high-quality, long-read de novo genome assembly to aid conservation of Hawaii’s last remaining crow species

Genome-level data can provide researchers with unprecedented precision to examine the causes and genetic consequences of population declines, and to apply these results to conservation management. Here we present a high-quality, long-read, de novo genome assembly for one of the worlds most endangered bird species, the Alala. As the only remaining native crow species in Hawaii, the Alala survived solely in a captive breeding program from 2002 until 2016, at which point a long-term reintroduction program was initiated. The high-quality genome assembly was generated to lay the foundation for both comparative genomics studies, and the development of population-level genomic tools that will aid conservation and recovery efforts. We illustrate how the quality of this assembly places it amongst the very best avian genomes assembled to date, comparable to intensively studied model systems. We describe the genome architecture in terms of repetitive elements and runs of homozygosity, and we show that compared with more outbred species, the Alala genome is substantially more homozygous. We also provide annotations for a subset of immunity genes that are likely to be important for conservation applications, and we discuss how this genome is currently being used as a roadmap for downstream conservation applications.

genomics↗