Scientists sequence DNA of Missouri cat
By Julie Bierach, KWMU
SAINT LOUIS, MO – This month, scientists published the DNA sequence of the Feline Genome. Researchers hope that by unveiling the genetic code of the domestic cat, they'll learn more about the 250 diseases that afflict both cats and humans.
As part of our series on genetics called "The DNA Files," KWMU's Science reporter, Julie Bierach visited with one special Missouri feline who will go down in history.
Inside a small room in a lab on the campus of the University of Missouri, Columbia, Cinnamon, a 4 year-old Abyssinian cat named for the color of her coat playfully paced in her steel cage.
Cinnamon has made scientific history. Scientists have decoded most of her DNA, making her an emblem for domestic cats everywhere.
"She's a very nice cat," said Dr. Kristina Narfstrom, a veterinarian at the University of Missouri-Columbia. "She's a little bit shy initially, but then when she gets to know you she becomes very nice and playful."
Dr. Narfstrom brought Cinnamon's parents to the U.S from Sweden, and has been breeding Abyssinians for her research for almost 25 years.
"She's actually the most inbred cat in the world," said Narfstrom, who is also a professor of veterinary ophthalmology. "And that is a good thing for such a project because then it's easier to sequence the cat genome."
Cinnamon has a degenerative eye disease that leads to blindness in both cats and humans. She's not blind, but does have vision problems. Dr. Narfstrom discovered the hereditary disease that causes rod cone degeneration in cats of Cinnamon's breed.
"Which means that the visual cells, the rods and the cones, die and this disease is very similar to human retinitis pigmentosa, which is a blinding disease then. And it affects one in 3,500 people worldwide," said Dr. Narfstrom.
And that's why Narfstrom says it's so important that the domestic cat genome has been sequenced.
Using Cinnamon's blood and tissue, Dr. Steven O'Brien and his team at the National Institutes of Health, sequenced and analyzed Cinnamon's DNA. O'Brien says just as humans and cats share similar organs like kidneys and heart, the genes are also organized in ways that are quite comparable.
"So by discovering, for example, the genetic basis of a disease, like diabetes in the cat, or a treatment or perhaps a better diagnostics, that can translate quickly to the same situation in many deadly human diseases that fill our hospitals for which we have little but symptomatic treatment today," said Dr. O'Brien, Director of the Laboratory of Genomic Diversity at the National Institutes of Health.
O'Brien and his team identified over 20,000 genes in the cat. During the analysis researchers, including Dr. Narfstrom, uncovered a mutation of a relatively unknown gene responsible for Cinnamon's retinitis pigmentosa.
"And this of course is exciting because it means that we now have a mechanism associated with the disease which will allow us to not only do screening better, but also to start thinking about therapy development, even gene therapy. And that kind of prospect is exactly why the genetic sequencing of these species is being accomplished," said O'Brien.
Back in the lab, Cinnamon purred as Dr. Narfstrom offered her a treat. Narfstrom's next effort will be to research a possible treatment for Cinnamon, gene therapy.
"Which means that we will be able to correct this defect by providing corrected cDNA for the actual gene that is not functioning as it is now," said Narfstrom.
For Dr. Narfstrom, the sequencing of the Feline genome has made her work a lot easier. For years she's tried to better understand these debilitating eye diseases that afflict humans through studies in her cats. And she says the sequencing of the Feline genome is a very significant breakthrough for those who study retinal diseases.
"Absolutely. Because it might provide help for severely impaired children in many ways, and also, of course, for the cats who are affected in the future," said Narfstrom.
And for Cinnamon, that's certainly good news.
Dr. Narfstrom and Cinnamon
This series is made possible with support from The DNA Files, a project of SoundVision Productions. More information is available at www.dnafiles.org.