Scientists Discover First Molecular Signature of Marfan Syndrome in Cats
Two brothers named Gary and Shaggy helped Cornell University researchers identify a rare genetic change linked to Marfan syndrome in domestic cats. In a study published in Scientific Reports, scientists reported the first molecular signature of the condition in cats, which is primarily recognized in humans.
Two cats with unusually long limbs led researchers to a rare discovery
Gary and Shaggy were first noticed as kittens because of their unusually long limbs. As they grew, veterinarians also identified abnormalities in their eye structure and an enlarged aorta, the body’s main artery. Together, these symptoms suggested Marfan syndrome, a genetic disorder that weakens connective tissue throughout the body.
Marfan syndrome affects about 1 in 4,000 people, but Gary and Shaggy were the first recorded cases identified in cats.
“The results of this study provide the basis for improved veterinary diagnostics,” said lead author Dr. Jacqueline Evans, assistant professor in the School of Veterinary Medicine and the Baker Institute of Animal Health. “It could help veterinarians recognize similar cases in the future and aid in the development of genetic tests.”
Researchers identify an unexpected FBN1 gene variant
To determine the cause of the brothers’ unusual symptoms, researchers from multiple disciplines conducted thorough medical examinations and analyzed their DNA. Their research identified a genetic change in FBN1, the gene that provides instructions for producing fibrillin-1.
Fibrillin-1 is essential for healthy connective tissue and helps support structures throughout the body, including blood vessels, bones, ligaments, skin and eyes.
Genetic testing revealed that Gary and Shaggy each carried two altered copies of FBN1, inheriting one from each parent. This is particularly noteworthy because, in humans, mutations in just one copy of the gene can cause Marfan syndrome. Having two altered copies is extremely rare and can severely disrupt normal fibrillin-1 production.
Why the cats survived into adulthood
The genetic changes in the siblings also had unexpected effects. Further analysis revealed that the variant did not completely disable the gene. Instead, it interfered with how the genetic instructions were processed while allowing some normal activity to continue.
This residual function may help explain why Gary and Shaggy survived into adulthood, even though having two copies of such a mutation could have resulted in more severe disabilities.
Source: www.sciencedaily.com