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bioRxiv · 10.1101/2020.11.15.384057

Desert Dingo (Canis lupus dingo) genome provides insights into their role in the Australian ecosystem.

Abstract

The dingo is Australias iconic top-order predator and arrived on the continent between 5,000-8,000 years ago. To provide an unbiased insight into its evolutionary affiliations and biological interactions, we coupled long-read DNA sequencing with a multiplatform scaffolding approach to produce an ab initio genome assembly of the desert dingo (85X coverage) we call CanLup_DDS. We compared this genome to the Boxer (CanFam3.1) and German Shepherd dog (CanFam_GSD) assemblies and characterized lineage-specific and shared genetic variation ranging from single- to megabase pair-sized variants. We identified 21,483 dingo-specific and 16,595 domestic dog-specific homozygous structural variants mediating genic and putative regulatory changes. Comparisons between the dingo and domestic dog builds detected unique inversions on Chromosome 16, structural variations in genes linked with starch metabolism, and seven differentially methylated genes. To experimentally assess genomic differences 17 dingoes and 15 German Shepherd dogs were fed parallel diets for 14 days. In dingoes, low AMY2B copy number and serum amylase levels are linked with high cholesterol and LDL levels. Gut microbiome analyses revealed enrichment of the family Clostridiaceae, which can utilize complex resistant starch, while scat metabolome studies identified high phenylethyl alcohol concentrations that we posit are linked with territory marking. Our study provides compelling genomic, microbiome, and metabolomic links showing the dingo has distinct physiology from domestic breed dogs with a unique role in the ecosystem.

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BibTeXRIS

Yadav, S., Dudchenko, O., Esvaran, M., Rosen, B. D., Field, M. D., Skvortsova, K., Edwards, R. J., Gopalakrishnan, S., Keilwagen, J., Cochran, B. J., Manandhar, B., Bucknall, M., Bustamante, S., Rasmussen, J. A., Melvin, R. G., Omer, A., Colaric, Z., Chan, E. K. F., Minoche, A. E., Smith, T. P., Gilbert, M. T. P., Bogdanovic, O., Zammit, R. A., Thomas, T., Aiden, E. L., Ballard, J. W. O.. 2020-11-16. Desert Dingo (Canis lupus dingo) genome provides insights into their role in the Australian ecosystem.. https://doi.org/10.1101/2020.11.15.384057

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