Researchers at the College of Veterinary Medicine and the Baker Institute of Animal Health have published the first molecular analysis of Marfan syndrome in domestic cats in the September 19 issue of Scientific Reports. This study, led by Dr. Jacquelyn Evans, an assistant professor in the Department of Biomedical Sciences, marks a significant step in veterinary medicine. It offers a foundation for better diagnostic tools and could lead to the development of genetic tests for the condition. Marfan syndrome is a rare, inherited disorder that affects connective tissues, which provide structure and support to various parts of the body. The research was prompted by two feline siblings, Gary and Shaggy, who exhibited unusually long limbs as kittens. Further examinations revealed eye abnormalities and an enlarged aorta, leading veterinarians to suspect Marfan syndrome. While the condition is well-documented in humans, this was the first known case in cats. Marfan syndrome in humans occurs in about 1 in 4,000 people and is caused by mutations in the FBN1 gene, which produces a protein called fibrillin-1. This protein is essential for the strength and elasticity of connective tissues. To understand the condition in cats, a team of veterinary specialists and genetic experts from the Baker Institute, the College of Veterinary Medicine, Ghent University in Belgium, the University of Pennsylvania, and the Schwarzman Animal Medical Center in New York City collaborated. Using clinical evaluations and genetic sequencing, they identified that Gary and Shaggy both carried two altered copies of the FBN1 gene. In humans, a single altered copy is sufficient to cause Marfan syndrome, but having two copies is extremely rare and typically more severe. However, in the case of these cats, the gene variant only partially disrupted the production of fibrillin-1, allowing the cats to survive into adulthood with less severe symptoms. The study highlights the value of interdisciplinary research and the role of pet owners in advancing scientific understanding. Dr. Evans emphasized that this discovery could benefit future veterinary care by improving diagnostics and treatment for similar cases. The research also demonstrates the importance of a "comparative approach," which uses insights from animal health to inform human medicine and vice versa. The findings were published by Shawna R. Cook and colleagues in Scientific Reports (2026), with the DOI: 10.1038/s41598-026-70702-3.