(EDIT: Whilst I was writing this, lauren001 found the same article in a different place)

The following (quite short) article is interesting:

http://www.winnfelinehealth.org/Page...plasia_Web.pdf

It mentions that the condition has been found in smaller breeds, end explicitly mentions Devon Rex.

It also points out that, as in dogs, there is no genetic test available to detect the fault. Testing in dogs is carried out by XRays being 'graded' by knowledgeable experts. This means that the condition can only ever be detected once it is manifest. If an individual carries one of the several defective genetic combinations that can lead to the condition, but has not yet manifested any unusual tissue deformity, there is simply no way of knowing that.

The article also states that most cats with the condition will not exhibit any discomfort or difficulty. Whilst this is good for the individual, it does suggest tat x-raying before breeding might be good, to ensure that the genetic makeup us not passed on unknowingly. However, that leads us on to the following...

Apparently, x-ray grading in felines is still very much in its infancy, an the article implies that there are only two centres offering this at present.

One is the University of Pennsylvania, offering PennHip testing, the other is the Hip Dysplasia Registry of the Orthopedic Foundation for Animals (OFA) at the University of Missouri.

This article was written in 2006, so thinks may well have progressed since then. I'll do a little more digging, and see what comes up...