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Yay for Platypus!

The genome of the Platypus has been sequenced:

The first analysis of the genome sequence of the duck-billed platypus was published today by an international team of scientists, revealing clues about how genomes were organized during the early evolution of mammals. The research was supported in part by the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health (NIH).

Fans of TV nature shows will remember that the duck-billed platypus, native to Australia, is one of the few mammals that lay eggs. However, platypus peculiarity does not end there. For example, these odd animals boast what looks like a duck’s bill, which houses an electrosensory system used when foraging for food underwater, and a thick fur coat to adapt to the icy waters in which it resides. Males also possess hind leg spurs that can deliver venom powerful enough to wound territorial competitors during mating season, or cause excruciating pain in other mammals, including humans.

“At first glance, the platypus appears as if it was the result of an evolutionary accident. But as weird as this animal looks, its genome sequence is priceless for understanding how fundamental mammalian biological processes have evolved,” said Francis S. Collins, M.D., Ph.D., director of NHGRI. “Comparisons of the platypus genome to those of other mammals will provide new insights into the history, structure and function of our own genome.”

In a paper published in today’s issue of the journal Nature, researchers analyzed a high-quality draft genome sequence of Glennie, a female platypus from Australia. The consortium included scientists from the United States, Australia, England, Germany, Israel, Japan, New Zealand and Spain. Sequencing of the platypus genome was led by the Genome Sequencing Center at Washington University School of Medicine in St. Louis, a part of NHGRI’s Large-Scale Sequencing Research Network.

Once the sequence was produced, researchers began comparing the genome of the platypus, whose ancestors split from the rest of mammalian lineage some 166 million years ago, with the well-characterized genomes of the human, mouse, dog, opossum and chicken, as well as the draft genome sequence of the green anole lizard. The chicken genome was chosen because it is descended from the ancestral group of egg-laying animals, including extinct reptiles, who passed on much of their DNA to animals like the platypus. Scientists were particularly interested in finding features within the platypus genome that could explain the odd mix of characteristics seen in the platypus: those that were more like reptiles, birds and mammals.

The team found that the platypus genome contains about the same number of protein-coding genes as other mammals — approximately 18,500. The platypus also shares more than 80 percent of its genes with other mammals whose genomes have been sequenced. Next, researchers combed the platypus genome looking for genetic evidence of sequences unique to platypuses that have been lost from mammalian genomes. Scientists were also eager to find out what characteristics of the platypus were linked at the DNA level to reptiles or mammals.

“The mix of reptilian, mammalian and unique characteristics of the platypus genome provides many clues to the function and evolution of all mammalian genomes,” said Richard K. Wilson, Ph.D., director of Washington University School of Medicine’s Genome Sequencing Center and the paper’s senior author. “Now, we’ll be able to pinpoint genes that have been conserved throughout evolution, as well as those that have been lost or gained.”

Read the rest here and the Nature article here

Comments

  1. #1 Cuttlefish
    May 7, 2008

    The genome of the platypus,
    We read today in Nature,
    Befits a beast so odd it once
    Defied our nomenclature;
    A mammal, but it still lays eggs,
    And you know what that means:
    The platypus and lizards share
    Some families of genes!
    Although the tale is quite complex–
    A long way off from solved–
    The genome of the platypus
    Shows how we all evolved!

  2. #2 Coturnix
    May 7, 2008

    Love it!!!!

  3. #3 Glendon Mellow
    May 8, 2008

    Wow, that’s such a sensational choice for sequencing. I hope it makes the mainstream news, it could draw attention to the field and issues of evolution in the public sphere in a good way.

    I agree: Yay for platypus!

  4. #4 Simarillion
    May 8, 2008

    I hope they do the echidna next! It would be interesting to learn how similar the monotremes are.

  5. #5 Mustafa Mond, FCD
    May 8, 2008

    It appears you found a much better-written article than I found:

    Neither fish nor fowl: Platypus genome decoded
    by Marlowe Hood
    …According to a study released Wednesday, the egg-laying critter is a genetic potpourri — part bird, part reptile and part lactating mammal.
    … missing link …
    But the peculiar mix of body features are clearly reflected in the animal’s DNA, the study found.

    The bird-like qualities implied by its Latin name, Ornithorhynchus anatinus, include webbed feet, a flat bill similar to a duck’s,…

    I think the journalist did their background research by reading Jack Chick tracts.

  6. #6 Nagraj
    May 8, 2008

    One more to the list of sequenced organisms..and its the animal i admire most..great….it will definitely help understanding evolution in mammals…….may be next one in line should be echnidia…….but they say no plans yet…so

  7. #7 Ian
    May 8, 2008

    Since there is only this one platypus, I’m always amused by references to “duck-billed”, like there was a “Horn-Billed” platypus or a “Spoon-billed” platypus at one time…!

    OTOH, who knows what the fossil record will turn up next!