The current status of genetic monitoring in conservation introductions

Type: Journal article

Reference: McLennan, E. A., Grueber, C. E., Belov, K., & Hogg, C. J. (2025). The current status of genetic monitoring in conservation introductions. Conservation Science and Practice, e70036. https://doi.org/10.1111/csp2.70036

Abstract

Conservation introductions, translocating species beyond their native range, are increasingly necessary. Because genetic diversity is essential for species to respond to novel environments, understanding whether establishing populations can maintain genetic diversity is crucial to the long-term success of conservation introductions. Using a systematic review, we quantified conservation introductions globally and assessed whether genetic monitoring is occurring. We found that, despite extensive discussion, conservation introductions were rare. Of 167 examples, most were performed in North America, Australia, and China, with megadiverse developing nations underrepresented. Plants were disproportionately represented (74%), and climate change was the primary motivator of conservation introductions (40%). Survival and reproduction were the most frequently measured outcomes (71% and 37%, respectively). Ten works (5.9%) reported genetic monitoring, of which only two considered temporal genetic data and showed a worrying trend of rapid negative genetic change post-establishment. With limited genetic evidence, it remains unclear whether conservation introductions can establish self-sustaining populations. As these translocations may be the only option for some species, we recommend conservation practitioners trial conservation introductions with temporal genetic monitoring to assess the maintenance of founding genetic diversity and inbreeding. Only through scientifically derived applications of conservation introductions will we learn how to establish self-sustaining populations in an uncertain future.

AMPed Up Immunity: 418 Whole Genomes Reveal Intraspecific Diversity of Koala Antimicrobial Peptides

Type: Journal article

Reference: Petrohilos C, Peel E, Silver LW, Belov K, Hogg CJ. AMPed up immunity: 418 whole genomes reveal intraspecific diversity of koala antimicrobial peptides. Immunogenetics. 2025 Jan 8;77(1):11. doi: 10.1007/s00251-024-01368-2.

Abstract

Characterising functional diversity is a vital element to understanding a species’ immune function, yet many immunogenetic studies in non-model organisms tend to focus on only one or two gene families such as the major histocompatibility complex (MHC) or toll-like receptors (TLR). Another interesting component of the eukaryotic innate immune system is the antimicrobial peptides (AMPs). The two major groups of mammalian AMPs are cathelicidins and defensins, with the former having undergone species-specific expansions in marsupials. Here, we utilised data from 418 koala whole genomes to undertake the first comprehensive analysis of AMP diversity across a mammalian wildlife species’ range. Overall, allelic diversity was lower than other immune gene families such as MHC, suggesting that AMPs are more conserved, although balancing selection was observed in PhciDEFB12. Some non-synonymous SNPs in the active peptide are predicted to change AMP function through stop gains, change in structure, and increase in peptide charge. Copy number variants (CNVs) were observed in two defensins and one cathelicidin. Interestingly, the most common CNV was the duplication of PhciCATH5, a cathelicidin with activity against chlamydia, which was more common in the southern part of the species range than the north. AMP copy number is correlated with expression levels, so we hypothesise that there is a selective pressure from chlamydia for duplications in PhciCATH5. Future studies should use phenotypic metadata to assess the functional impacts of this gene duplication.

Spatial variation in toll-like receptor diversity in koala populations across their geographic distribution

Type: Journal article

Reference: Cui J, Batley KC, Silver LW, McLennan EA, Hogg CJ, Belov K. Spatial variation in toll-like receptor diversity in koala populations across their geographic distribution. Immunogenetics. 2024 Nov 30;77(1):5. doi: 10.1007/s00251-024-01365-5

Abstract

The koala (Phascolarctos cinereus) is an iconic Australian species that is listed as endangered in the northern parts of its range due to loss of habitat, disease, and road deaths. Diseases contribute significantly to the decline of koala populations, primarily Chlamydia and koala retrovirus. The distribution of these diseases across the species’ range, however, is not even. Toll-like receptors (TLRs) play a crucial role in innate immunity by recognising and responding to various pathogens. Variations in TLR genes can influence an individual’s susceptibility or resistance to infectious diseases. The aim of this study was to identify koala TLR diversity across the east coast of Australia using 413 re-sequenced genomes at 30 × coverage. We identified 45 single-nucleotide polymorphisms (SNP) leading to 51 alleles within ten TLR genes. Our results show that the diversity of TLR genes in the koala forms four distinct genetic groups, which are consistent with the diversity of the koala major histocompatibility complex (MHC), another key immune gene family. The bioinformatics approach presented here has broad applicability to other threatened species with existing genomic resources.

The Amphibian Genomics Consortium: advancing genomic and genetic resources for amphibian research and conservation

Type: Journal article

Reference: Kosch, T.A., Torres-Sánchez, M., Liedtke, H.C. et al. The Amphibian Genomics Consortium: advancing genomic and genetic resources for amphibian research and conservation. BMC Genomics 25, 1025 (2024). https://doi.org/10.1186/s12864-024-10899-7

Abstract

Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomic resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomic resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, anti-predator strategies, and resilience and adaptive responses. They also serve as essential models for studying broad genomic traits, such as evolutionary genome expansions and contractions, as they exhibit the widest range of genome sizes among all animal taxa and possess multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The emergence of long-read sequencing technologies, combined with advanced molecular and computational techniques that improve scaffolding and reduce computational workloads, is now making it possible to address some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC, https://mvs.unimelb.edu.au/amphibian-genomics-consortium) in early 2023. This burgeoning community already has more than 282 members from 41 countries. The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and call on the research and conservation communities to unite as part of the AGC to enable amphibian genomics research to “leap” to the next level.

Building meaningful collaboration in conservation genetics and genomics

Type: Journal article

Reference: Shaw, R.E., Brockett, B., Pierson, J.C. et al. Building meaningful collaboration in conservation genetics and genomics. Conserv Genet 25, 1127–1145 (2024). https://doi.org/10.1007/s10592-024-01636-4

Abstract

Genetic diversity is the foundation of biodiversity, and preserving it is therefore fundamental to conservation practice. However, global conservation efforts face significant challenges integrating genetic and genomic approaches into applied management and policy. As collaborative partnerships are increasingly recognized as key components of successful conservation efforts, we explore their role and relevance in the Australian context, by engaging with key entities from across the conservation sector, including academia, botanic gardens, herbaria, seed banks, governmental/non-governmental organisations, private industry, museums, Traditional Owners, Indigenous rangers, and zoos and aquaria. By combining perspectives from these entities with comprehensive literature review, we identified five guiding principles for conservation genetic and genomic research and explored the different elements of, and approaches to, collaboration. Our reflections suggest that there is a substantial overlap in research interests across the Australian conservation sector, and our findings show that collaboration is increasing. We discuss approaches to building collaborative partnerships, the reciprocal benefits of collaborating, and some remaining challenges associated with data generation, data collection, and cross-cultural considerations. We emphasise the need for long-term national resourcing for sample and data storage and consistency in collecting, generating and reporting genetic data. While informed by the Australian experience, our goal is to support researchers and practitioners to foster meaningful collaborations that achieve measurable management outcomes in conservation genetics and genomics, both in Australia and globally.

Extant and extinct bilby genomes combined with Indigenous knowledge improve conservation of a unique Australian marsupial

Type: Journal article

Reference: Hogg, C.J., Edwards, R.J., Farquharson, K.A. et al. Extant and extinct bilby genomes combined with Indigenous knowledge improve conservation of a unique Australian marsupial. Nat Ecol Evol 8, 1311–1326 (2024). https://doi.org/10.1038/s41559-024-02436-2

Abstract

Ninu (greater bilby, Macrotis lagotis) are desert-dwelling, culturally and ecologically important marsupials. In collaboration with Indigenous rangers and conservation managers, we generated the Ninu chromosome-level genome assembly (3.66 Gbp) and genome sequences for the extinct Yallara (lesser bilby, Macrotis leucura). We developed and tested a scat single-nucleotide polymorphism panel to inform current and future conservation actions, undertake ecological assessments and improve our understanding of Ninu genetic diversity in managed and wild populations. We also assessed the beneficial impact of translocations in the metapopulation (N = 363 Ninu). Resequenced genomes (temperate Ninu, 6; semi-arid Ninu, 6; and Yallara, 4) revealed two major population crashes during global cooling events for both species and differences in Ninu genes involved in anatomical and metabolic pathways. Despite their 45-year captive history, Ninu have fewer long runs of homozygosity than other larger mammals, which may be attributable to their boom–bust life history. Here we investigated the unique Ninu biology using 12 tissue transcriptomes revealing expression of all 115 conserved eutherian chorioallantoic placentation genes in the uterus, an XY1Y2 sex chromosome system and olfactory receptor gene expansions. Together, we demonstrate the holistic value of genomics in improving key conservation actions, understanding unique biological traits and developing tools for Indigenous rangers to monitor remote wild populations.