Inherited blindness (PRA)
The light-sensitive cells at the back of the eye slowly fade, so the cat goes blind over several years. Only a cat with two copies of the gene is affected. Two forms have been found in the Highlander: about 1 in 30 cats tested carry one, about 1 in 200 the other. No sick Highlanders have been reported yet.
How it is found: DNA test of the parents, for both forms.






