A WHALE OF A TALE - A DNA DETECTIVE STORY Dr Karobi Moitra , NCI Frederick
Where do whales stand on the tree of life? Kingdom: Animalia Phylum: Chordata Sub phylum: Vertebrata Class: Mammalia Order: Cetacea (Gk Cetus) Suborder: Odontoceti Toothed whales Eg:Killer whale Suborder: Mysticeti Baleen whales Eg:Blue whale
How do we stop hunting of endangered species? CITES : Convention on International Trade in Endangered Species Of Wild Flora and Fauna Formed in 1973 and came into force in 1975 it works by controlling international trade in endangered species and Forbids/restricts any trade in selected species including the following species of whale: fin whales, sei whales, humpback whales, Brydes whales,blue whales, Asian gray whale and certain populations of Minke whales.
Detective work - elementary my dear Watson! Scott Baker came up with a plan and enlisted the help of Naoko Funahashi a Japanese conservationist For a long time Greenpeace and Earthtrust had suspicions the whale meat (kujira)sold in Japanese markets was from endangered species but how to prove it? What do you think the plan was?
Problems: <ul><li>To identify the different species of whale from whale meat </li></ul><ul><li>None of the whale meat can be taken out of Japan </li></ul><ul><li>To convince Japan based on the evidence to control illegal </li></ul><ul><li>whaling </li></ul>
<ul><li>To identify the different species of whale from samples </li></ul><ul><li>of whale meat sold in the markets </li></ul>
2. None of the whale meat can be taken out of Japan to Scotts lab at NCI Frederick Need to copy the whale DNA How would you do that?
PCR Copying DNA Starting DNA Template 5’ 5’ 3’ 3’
The Polymerase Chain Reaction <ul><li>PCR, or the polymerase chain reaction, makes copies of a specific </li></ul><ul><li>piece of DNA </li></ul><ul><li>PCR allows you to look at one specific piece of DNA by making </li></ul><ul><li>copies of *only* that piece of DNA </li></ul><ul><li>PCR is like looking for a needle in a haystack, and then making a </li></ul><ul><li>haystack out of the needle </li></ul>
The Plan : Naoko went to the markets & stuffed whale meat into little glass vials labeled with the name and the market location Scott made an improvised genetics lab in his Tokyo hotel room and copied the DNA from the whale meat using PCR He then took the DNA ran it on a gel and took only the copied DNA with him leaving the originals or ‘templates’ behind.
Fin whales Sei whales Humpback whales Brydes whales Blue whales Asian gray whale Minke whales. X Species (DNA sequence) ATTTTAGGGGTACC etc. ATTTTAGGGGTACC
The Results Sequencing of the DNA revealed that a no. of endangered species of whale including fin whales, sei whales, humpbacks Brydes whales , blue whales and minke whales were being Illegally hunted Scott convinced the Japanese government to monitor their catch of whales using modern molecular biology methods to make sure that endangered species were not being hunted