Or, ya know, hypothetically, the simplest explanation is the correct one. Pinstripe is a dominant mutation, so the homozygous form has the same phenotype as the heterozygous form.

Nobody bothers with the pairing because youd either have to keep every pin and prove it out, even your low value single gene males. Or you'd sell all the animals as just pinstripe and potentially sell a homozygous pin and someone else would reap the benifit of your project with you getting no benefit.

In the cost/benefit analysis of trying a pairing like this there is really no benefit aside from satisfying your own curiosity. Thats why nobody ever tries stuff like this. So good on ya @ the OP!

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