Genetic Polymorphism in Caseins of Cows’ Milk. II. Confirmation of the Genetic Control of β-Casein Variation

Abstract

Examination of the caseins from 1,349 individual cows of the five major dairy breeds in the United States showed that the A and B alleles of β-casein occur in Jerseys and Holsteins. The A, B, and C alleles occur in the Guernsey and Brown Swiss breeds. Only the A allele has been found in the Ayrshire breed. These results confirm the discovery of β-casein polymorphism by Aschaffenburg (1, 2) and support his conclusion that the variability has a genetic basis. © 1964, American Dairy Science Association. All rights reserved.