UC Davis School of Veterinary Medicine Veterinary Genetics Laboratory


Scottish Fold

The Scottish Fold breed has cats with both strait and folded ear phenotypes. The fold type results from a mutation in a single gene. The mutation is dominant and a single copy of the mutation affects cartilage development and produces the fold phenotype. All fold kittens are born with straight ears. Ear folding starts as early as 3 weeks of age. Other impacts of the mutation are variable but most consistently present as smaller feet resulting from misshapen toes, thickened and inflexible tails and accelerated progressive osteoarthritis. Age of onset and progression of secondary effects are highly variable but ear folding is a consistent feature. Kittens with two copies are prone to more extreme health problems affecting cartilage and bone.

Research by Dr. B. Gandolfi in the laboratory of Dr. Leslie Lyons, University of Missouri, identified the mutation associated with the fold phenotype. The VGL offers a DNA test for Scottish Fold to assist owners and breeders to confirm presence and number of copies of the Fold mutation in young kittens. Knowledge of the genotype status will inform potential risk for future health problems.

Genetic testing for this Fold mutation is recommended for Scottish Folds.

Procedure for collecting a feline DNA sample

Allow 2-6 business days for results.

Results are reported as:

Test Result Scottish Fold
N/N No copies of the fold mutation
N/SF Affected - 1 copy of the Fold mutation; cat will have folded ears
SF/SF Affected - 2 copies of the Fold mutation; cat will have folded ears and may have severe bone and joint issues


Manuscript in preparation: Causative mutation identified by Dr. B. Gandolfi in the laboratory of Dr. Leslie Lyons.




Veterinary Genetics Laboratory, Tel 530-752-2211, Email VGL