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Genetic testing

Methods that genotype the CSN2 (beta-casein) gene from a cow's DNA.

Why genotype?

A2-only milk is produced by herds that are homozygous A2/A2. Selective breeding requires reliable identification of A2/A2, A1/A2, and A1/A1 cows, which is best done at the DNA level rather than by repeated milk testing.