The Pinstripe is a dominant morph, not a co-dominant, because it does not have a super form, that looks different than the regular Pinstripe.
To be more specific, to get a Pinstripe, the pinstripe gene must be passed down from either the sire or the dame. In theory, if BOTH, the sire and dame, pass the pinstripe gene, there should be a super pinstripe. To this day, people have tried, and there has never been a pinstripe to pinstripe mating that has produced anything looking different from the pinstripe or the normal. I.E. No visible supers have ever been seen.
This implies either 1) The super form looks just like the standard pinstripe, or 2) there is absolutely no such thing as a super pinstripe, which could only happen if somehow a female follicles, if possessing the pinstripe gene, can somehow reject any male sperm containing the same gene.
I personally do not see how option 2 is possible, but I’m no geneticist. Therefore, I am going with the assumption, that the super form of the pinstripe looks just like the normal pinstripe, but nobody has taken the time needed to prove one out.
I cannot say “nobody”. I keep hearing rumors of some breeder that has a genetic super pinstripe (still not a visual difference from the regular pinstripe.)
All that said, this year (2012) I paired a male Pinstripe to a female Pinstripe, and produced 3 pinstripe looking hatchlings. Of these, two are male, and one is female.
The rest of this project will take place in the years to come. When these hatchlings are big enough to breed, I will be watching for one or more of them to pass the pinstripe gene to 100% of their offspring. This is going to be difficult to prove, but if a single offspring does NOT receive the pinstripe gene, it will disqualify it’s parent from further tests.
Wish me luck!