DairyTalk 141: When Red × Red Turns Black - Understanding the COPA Variant Red Gene - by Helmut Demmelhuber

Variant Red genetics aren’t just a color curiosity — they’re a
costly trap for breeders who don’t understand the COPA gene.
Acting as an epistatic override, COPA can switch red animals back
to black, even when both parents appear genetically red. The
result: unpredictable offspring, registration mistakes, and
disappointed buyers. Genomic testing for both COPA and MC1R is
now essential for anyone who wants reliable color outcomes and
professional credibility in the seedstock business. With comments
on a "The Bullvine"-article (Dezember 1st, 2025) by Andrew Hunt:
https://www.thebullvine.com