Molecular Characterization of Bovine CSN1S2B and Extensive Distribution of Zebu-Specific Milk Protein Alleles in European Cattle

• Published in: Journal of dairy science Vol. 90; no. 7; pp. 3522 - 3529
• Main Authors: Ibeagha-Awemu, E.M., Prinzenberg, E.-M., Jann, O.C., Lühken, G., Ibeagha, A.E., Zhao, X., Erhardt, G.
• Format: Journal Article
• Language: English
• Published: Savoy, IL Elsevier Inc 01.07.2007; American Dairy Science Association; Am Dairy Sci Assoc
• Subjects: Alleles; amino acid sequences; Animal productions; Animals; Biological and medical sciences; Bos; Caseins - genetics; cattle; Cattle - genetics; cattle breeds; DNA Primers - chemistry; Europe; European cattle; exons; Female; Food industries; Fundamental and applied biological sciences. Psychology; Gene Frequency - genetics; Genetic Variation; Genotype; haplotypes; Lactalbumin - genetics; loci; Milk and cheese industries. Ice creams; milk proteins; Milk Proteins - genetics; molecular conformation; molecular sequence data; Polymerase Chain Reaction - veterinary; Polymorphism, Single Nucleotide; Sequence Analysis; Terrestrial animal productions; Vertebrates; zebu; zebu breeds; zebu-specific alleles; αS2-casein; Europe; αS2-casein; haplotypes; zebu-specific alleles; Bos; Farming animal; Bovine; Characterization; Vertebrata; Allele; Milk protein; Mammalia; Casein; Zebu; Distribution; Dairy industry; Zebu milk; Livestock; αs2-casein; Artiodactyla; Haplotype; Ungulata
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.2006-679

The B allele of the bovine αS2-casein gene (CSN1S2) was characterized at the molecular level and the distribution of zebu-specific milk protein alleles was determined in 26 cattle breeds originating from 3 continents. The CSN1S2 *B allele is characterized by a C → T transition affecting nucleotide 17 of exon 3, which leads to a change in the eighth amino acid of the mature protein, from Ser to Phe (i.e., TCC →TCC). DNA-based methods were developed to identify carriers of CSN1S2*B and the other alleles (CSN1S2 *A, C, and D) at the same locus. CSN1S2*B and other zebu-specific milk protein alleles and casein haplotypes are widely distributed in European cattle breeds, particularly those of southeastern origin. Alleles CSN1S2 *B and CSN3*H are important in searching for zebu imprints in European cattle breeds. Diversity estimates at the milk protein loci were highest in the zebus followed by southeastern European taurines. Anatolian Black had the highest number of zebu alleles among European taurines. Common, group, and intergroup haplotypes occurred in the breeds and demonstrated relationships that concurred with developmental histories, genetic makeup, and, in particular, exposed the extent of zebu influence on southeastern European cattle.