Have you ever seen a white tiger? Maybe you have in a zoo, but that too has been quiet rare. In the Indian subcontinent, tigers have been popular since than the 1500's, but the white tiger has been rarer than ever after the last known one in the wild was shot in 1958. White tigers create an incredible genetic diversity. Although, they are sometimes known to have abnormalities (mostly due to human doings), they were suitable for the wild life and were able to survive. Over hunting greatly decreased their population across the world.
To help preserve the amazing white tiger population, Shu-Jin Luo and his colleagues from Peking University in China, created a captive management program. They took 16 tigers, then sequenced them with the genomes of the three parent tigers of the batch. Using genetic analysis, they discovered a pigment called SLC45A2. This is the pigment which affects coloration and is in light organisms. The pigment found in the white tiger mostly inhibits the synthesis of
red and yellow pigments but has barely any effect on black, which
explains why white tigers still show characteristic dark stripes. Using this pigment, scientists now hope to greater explore the reasons to how and why tigers are able to maintain both of the separate colors.
NOS Themes:
Science is collaborative - The colleagues from Peking University worked together to discover the new pigment.
Science is based on evidence - Based on evidence from the past that the white tigers lived in the wild before, scientists were able to conclude that white tigers are fit for the wild and are genetically very diverse.
Science is experimental - After experimenting with sequencing, scientists discovered the new pigment.
Article:
http://www.sciencedaily.com/releases/2013/05/130523143342.htm
Additional Articles:
http://www.bbc.co.uk/news/science-environment-22638341
http://blogs.smithsonianmag.com/smartnews/2013/05/one-slight-genetic-tweak-gave-white-tigers-their-pale-coats/
I researched on the pigment called SLC45A2. Although you provided the function of this pigment as "the pigment which affects coloration and is in light organisms". To add more, it makes proteins called melanin in the cells, melanocytes. In the site I visited, it states that the actual function of this protein is unknown, but it does participate in making the protein that gives hair, skin, and eye, color.
ReplyDeletehttp://ghr.nlm.nih.gov/gene/SLC45A2
I wondered why the white tiger is so rare and to add to your articles I found out that whites tigers need to be inbred (like brother-sister or through generations)which causes defects such as the white coat. Even inbreeding though does not assure the white coloring, the gene is a double recessive gene making it very hard for it to appear. The inbreeding can also cause a wide range of other genetic issues as well keeping the population at a minimum.
ReplyDeletehttp://bigcatrescue.org/abuse-issues/issues/white-tigers/
Rachel Nelson -Hour 1
I looked at your link Rachel, and found that really interesting. But it also got me wondering if the change in color caused by in breeding is nessacarily a "defect"? I can understand genetic issues mentally, but I'm not to sure how color change would be so bad. So I decided to do some research on inbreeding animals and the consequenses of their actions.
ReplyDeleteHeres the link: http://extension.missouri.edu/publications/DisplayPub.aspx?P=G2911