ArticleGenome biology2007
The multiple sex chromosomes of platypus and echidna are not completely identical and several share homology with the avian Z.
Article in Genome biology, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 63 papers.
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63 citing papers in PubMed, 141 citations in OpenAlex.
- Best practices for improving alignment and variant calling on human sex chromosomes.American journal of human genetics · 2026Article
- Investigating the evolution of large meiotic rings of multiple X and Y sex chromosomes in two Leptodactylus frog species (Anura, Leptodactylidae).Communications biology · 2025Article
- The Tree of Sex consortium: a global initiative for studying the evolution of reproduction in eukaryotes.Journal of evolutionary biology · 2025Article
- AMHY and sex determination in egg-laying mammals.Genome biology · 2025Article
- Chromosome-level echidna genome illuminates evolution of multiple sex chromosome system in monotremes.GigaScience · 2025Article
- Color vision evolution in egg-laying mammals: insights from visual photoreceptors and daily activities of Australian echidnas.Zoological letters · 2024Article
- Chromosome-level genome and the identification of sex chromosomes in Uloborus diversus.GigaScience · 2022Article
- GENESPACE tracks regions of interest and gene copy number variation across multiple genomes.eLife · 2022Article
- Sex chromosome evolution among amniotes: is the origin of sex chromosomes non-random?Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- Multiple sex chromosomes in teleost fishes from a cytogenetic perspective: state of the art and future challenges.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Review
- A brief review of vertebrate sex evolution with a pledge for integrative research: towards 'Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Review
- Review
- Evolution, Expression and Meiotic Behavior of Genes Involved in Chromosome Segregation of Monotremes.Genes · 2021Article
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- Review
- Genetic diversity, demographic history and neo-sex chromosomes in the Critically Endangered Raso lark.Proceedings. Biological sciences · 2020Article
- Ancestral male recombination in Drosophila albomicans produced geographically restricted neo-Y chromosome haplotypes varying in age and onset of decay.PLoS genetics · 2019Article
- Germline-Specific Repetitive Elements in Programmatically Eliminated Chromosomes of the Sea Lamprey (Genes · 2019Article
- Sex chromosome quadrivalents in oocytes of the African pygmy mouse Mus minutoides that harbors non-conventional sex chromosomes.Chromosoma · 2019Article
- Identifying, understanding, and correcting technical artifacts on the sex chromosomes in next-generation sequencing data.GigaScience · 2019Article
3 more citing papers are in PubMed but not listed here.
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Authors and funding
13 authors at 4 institutions in 3 countries.
Funding
Abstract
backgroundSex-determining systems have evolved independently in vertebrates. Placental mammals and marsupials have an XY system, birds have a ZW system. Reptiles and amphibians have different systems, including temperature-dependent sex determination, and XY and ZW systems that differ in origin from birds and placental mammals. Monotremes diverged early in mammalian evolution, just after the mammalian clade diverged from the sauropsid clade. Our previous studies showed that male platypus has five X and five Y chromosomes, no SRY, and DMRT1 on an X chromosome. In order to investigate monotreme sex chromosome evolution, we performed a comparative study of platypus and echidna by chromosome painting and comparative gene mapping.
resultsChromosome painting reveals a meiotic chain of nine sex chromosomes in the male echidna and establishes their order in the chain. Two of those differ from those in the platypus, three of the platypus sex chromosomes differ from those of the echidna and the order of several chromosomes is rearranged. Comparative gene mapping shows that, in addition to bird autosome regions, regions of bird Z chromosomes are homologous to regions in four platypus X chromosomes, that is, X1, X2, X3, X5, and in chromosome Y1.
conclusionMonotreme sex chromosomes are easiest to explain on the hypothesis that autosomes were added sequentially to the translocation chain, with the final additions after platypus and echidna divergence. Genome sequencing and contig anchoring show no homology yet between platypus and therian Xs; thus, monotremes have a unique XY sex chromosome system that shares some homology with the avian Z.
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